Stormtrooper

"I smoke Cohibas, you smoke cock."

"I don't care how many there are, FIGHT!"

– Kasrkin Sergeant McNeil, shortly before being overrun.

"Are we blind!? DEPLOY THE GARRISON!!!"

– Director Orson Krennic, Rogue One

Stormtroopers (Sturmtruppen) were specialist close assault raiders in the German army during World War I. It is also the English name of the Sturmabteilung, the notorious paramilitary arm of the Nazi party, leading to the common misconception that the term "Stormtrooper" originates with Nazis when, as already said, WWI Germans used it first. Their Nazi / Imperial German connotations, plus a cool name that's historical and thus freely usable, means they show up a lot as fictional specialist units. The (somewhat misinformed) association with the Nazis makes fictional units bearing this name more likely to be part of less than benevolent governments with the good guy factions usually calling them Shock Troopers or some variant thereof. A sub-type of Godwin's Law is using the word "Stormtrooper" as an insult to describe someone perceived as an authoritarian doucebag, especially if they're authority figures.

All of this leads us to...

Warhammer 40,000

In Warhammer 40,000, Stormtroopers (officially called Tempestus Scions because trademarks and, ironically Guardsmen in German because... reasons) are the elite of the Imperial Guard and the core of the Militarum Tempestus; they're the best general-combat infantry that the Imperial Guard can field, and are the toughest, best-equipped, and best-trained soldiers available to an Imperial commander that isn't a SPESS MEHREEN. While most of the Guard is armed with your typical angry flashlight and Flak Armor or Flak Vest, Stormtroopers normally pack Hotshot Lasguns, which fire much more penetrating shots that are capable of piercing most infantry armor with ease, and they are clad in Carapace Armor, which gives them substantially higher survivability on the battlefield (Cadian Kasrkin wear the more Chad Kasrkin 'Cat' Armour).

In earlier editions of the game, they were favored as "Light Marines" since they had fairly similar performance to Space Marines but cost considerably less due to their weaker gear. As of 6th edition, they became a dedicated elite choice, with all the pros and cons that implies. Unless you use their own mini-codex, of course. Then they become troops. In 8th edition, they became Troops even if you didn't.

There is a key difference between true Stormtroopers and many different types of regimental proxies/wannabies, the former originate from Schola Progenium, the latter are simple top-notch regimental soldiers. There is also a line between Stormtroopers analogues and Grenadiers (or Heavy Infantry Regiments): Cadia for example fields Kasrkin, Armageddon fields Steel Legion Stormtroopers, Death Korps of Krieg field Grenadiers (all three of those are armed with hellguns instead of hotshots), but the Harakoni Warhawks are grenadiers by Guard classification, armed with humble lasguns and not expected to meet Stormtroopers standards despite being clad in Carapace Armor. The Inquisition also fields their own branch called the "Inquisitorial Stormtroopers" who form the Inquisition's main offensive force and are basically the 5% of Schola Progenium Stormtroopers deemed pure, faithful and overall good enough to help your average Inquisitor meet the horrors that are part of his job head-on. Regardless of their appearance or gear, they're all incredibly potent if used correctly. Unfortunately, in terms of actual models, the only stormtroopers you can currently get (besides the Death Korps Grenadiers) are the Tempestus Scions and Kasrkin.

While this sounds all proper and awesome, the average Guardsman in the street can't stand them, referring to them as "glory boys" and resenting the fact that they're a good deal less likely to die, given that they're given better equipment than standard issue cardboard armor with a flashlight. Perhaps also viewing the Stormtroopers as intruding on the Imperial Guard’s role as the successor to the Imperial Army’s ground forces. The Kasrkin (and probably Death Korps Grenadiers, since dead men don't care for glory), who are revered and respected amongst Cadia, are a curious exception. This is likely due to the fact that, unlike most stormtroopers, who are raised and trained in the prestigious Schola Progenium, Kasrkin are all trained right on Cadia and experience the same hellish conditions as everyone else, so they also strongly believe that THIS WILL BE DA DAY UF GLOREE. More canonically, it is because Kasrkin have the same equipment as the grunt Guardsmen they serve with except they have a hellgun - and yet in spite of the shitty everything else, they're WAY more badass than the stormtroopers. That is why they are inspiring to the average Guardsmen: Kasrkin show them what normal humans can really do, even the Imperial Guard.

If the Imperial Guard are the levies of the Imperium, the Tempestus Scions are the Imperium’s professional army.

Notable Stormtrooper Regiments

• 9th Ioatan Gorgonnes: The 9th Ioatan Gorgonnes come from the Schola Progenium facility on Vedill I, the same facility that feeds recruits to the Order of the Glowing Chalice. Though they part ways upon finishing their training, they are always reunited on the battlefield. As a result, the 9th Ioatan Gorgonnes are often seen doing missions on behalf of the Ecclesiarchy.
• 22nd Thetoid Gryphonnes: The 22nd Thetoid Gryphonnes are all orphans from the world of Tallix, which has higher than normal gravity. This gives them stronger leg muscles than normal and allows them to perform rapid assaults on any terrain, even with heavy gear. They've also modified their Taurox Primes to sacrifice armor for additional speed.
• 32nd Thetoid Eagles: The 32nd Thetoid Eagles were known for their secretive nature and brutality in battle, with concerns growing among Segmentum command over their ability to follow orders. When the regiment was deployed to the Xinon System to put down an Alpha Legion cultist uprising, the regiment's command structure and Commissar were killed by a war machine hiding in lava. After securing a drop zone for the 32nd Elysian Drop Troops as originally ordered, the regiment went berserk and put down uprising after uprising. When the Elysians tried to debrief the 32nd Thetoid Eagles, they found that the entire regiment had vanished.
• 33rd Deltic Phoenixes: The 33rd Deltic Phoenixes were formed from children orphaned by Dark Eldar raids on the planet Kaldamor. Despite having their memories wiped, the regiment displays a greater zeal and kill rate against Dark Eldar. The Kabal of the Emerald Talon has vowed revenge against the regiment after being defeated by them on the world of Erendix.
• 34th Betic Centaurs: The 34th Betic Centaurs are based on the volcanic Death World of Makron V, which is often raided by Chaos forces. These raids help produce some of the hardiest and most battle-hardened stormtroopers in the Imperium, as they provide a perfect training opportunity for the Schola Progenium.
• 34th Psian Vipers: The 34th Psian Vipers are known for their tenacity, even by Ordo Tempestus standards. When the regiment was deployed against awakening Necrons on the Agri-World of Murunda II, they got trapped underground when the main entrances collapsed. They didn't consider their escape options until they had destroyed every Necron on the world after several weeks of nonstop fighting.
• 43rd Iotan Dragons: The stormtroopers of the 43rd Iotan Dragons train within simulated darkened labyrinths that give them the ability to fight totally blind. This has made them successful against numerous stealthy enemies, especially Tyranid organisms.
• 50th Kappic Eagles: Despite barely numbering a single company, the 50th Kappic Eagles have become renowned for their bravery and fearlessness in the face of overwhelming odds under the command of Tempestor Prime Salem Whitlock. Whitlock always insists on leading from the front, and his bravery inspires his men to victory after victory.
• 54th Psian Jackals: After Hive Fleet Leviathan ate their original homeworld, the 54th Psian Jackals set up shop on the Maiden World of Mayloc. The Eldar didn't take too kindly to this, and have attacked them multiple times to retake their land. These attacks have turned the 54th Psian Jackals into the best of the best within the Ordo Tempestus for tracking and countering Eldar incursions, and they have been deployed to deal with Eldar from various Craftworlds. They also like to paint skulls on their helmets and other images across their armour to intimidate their enemies.
• 55th Alphic Hydras: Among the most respected of Stormtrooper regiments, and bros with the Ultramarines. In fact, they're so close with the Ultramarines that they've been given extra training grounds across the Ultramar sub-sector. It's even been rumored that the regiment sends its best and youngest Stormtroopers to be initiated into the chapter. The 55th Alphic Hydras first gained recognition after being deployed alongside the Ultramarines 2nd Company and single-handily purging the Agri-World Masali of Orks. The Chaplain assigned to the 2nd Company quickly realized the regiment's value, and they have been deploying alongside the Ultramarines at their request ever since.
• 55th Kappic Eagles: The posterboy Stormtrooper regiment seen on all the box art. They pretty much have no personality beyond being really good at their jobs.
• 62nd Rhoin Cobras: Have a diehard hatred of all forms of foul sorcery. They once had to protect their former Schola Progenium facility on the Jungle World of Skell II from the Thousand Sons. Despite losing half the regiment, the Stormtroopers were successful in saving their former home.
• 68th Deltic Lions: The Stormtroopers of this regiment are known for being extremely hardy and resistant to disease, and they're often deployed to Zone Mortalis battlefields and alongside the Ordo Malleus to fight the forces of Nurgle. Nurgle has taken quite the interest in this regiment, and seeks to test and investigate them with all sorts of Daemons.
• 86th Deltic Dragons: When the Imperium is forced to cooperate with the Tau to deal with an even greater xenos threat, it's the 86th Deltic Dragons that are sent in. The 86th Deltic Dragons often deploy alongside the similarly stoic and determined forces of Sept Kel'shan. The two forces have successfully defended two separate worlds from splinter fleets of Hive Fleet Gorgon, with the 86th Deltic Dragons getting in close to deal with the big targets and bolstering the Tau gunlines in close range firefights. The Ordo Tempestus watches the regiment closely, and forbids Tempestor Prime Prellus from communicating with Tau Commander Shas'O Shi'Y'he.
• 88th Alphic Lions: Bros to the end with the Blood Angels, and specialists in dealing with Warp-based entities.
• 101st Betic Dragons: The 101st Betic Dragons are renowned for their skill in airborne strike assaults. They used those skills to harry and drive some Helbrutes of the Crimson Slaughter into lava on a volcanic Death World, and gave the Destroyers chapter the boost they needed to defeat the Chaos Space Marines.
• 133rd Lambdan Lions: The Schola Progenium and training facilities of the 133rd Lambdan Lions are based on the two moons that orbit the Forge World of Mezoa. Ancient pacts between Mezoa and the Ordo Tempestus see the 133rd Lambdan Lions deployed on behalf of Mezoa's priesthood to recover lost technologies. In exchange, Mezoa augments the gear and vehicles of the regiment, and even teaches them basic Lingua-technis. Despite this, the regiment has little interaction with the Cult Mechanicus and only gives a shit about what their next orders are. Unlike most Stormtrooper regiments, the 133rd Lambdan Lions will engage in long expeditionary campaigns rather than quick strikes as part of their tech recovery missions. Depending on the situation they will also fight in the shadow of Skitarii Legions and the Adeptus Titanicus, although they usually just do the bidding of Mezoa with the approval of the Ordo Tempestus. Occasionally, the Adeptus Mechanicus will go behind the back of the Ordo Tempestus and issue orders without waiting for approval if Imperial bureaucracy really kicks in.

In Dawn of War

Kasrkin are available for the Imperial Guard starting in Winter Assault, and they're one of the better choices the Guard has. They suffer the same problem that almost every unit in Winter Assault has, however, in that they're redundant - they utterly replace Guardsmen by Tier 3 in that game, and in every game of WA that makes it that far, your sole mission objective from then on is to spam Kasrkin endlessly.

In the later games - Dark Crusade and Soulstorm - their numbers were hardcapped, ergo ensuring that you can only use one squad at a time. They were also added in as a main unit in the Inquisition Daemonhunt mod/Ultimate Apocalypse, and made hideously OP after Dark Crusade's infamous moving debuff, as their ridiculous rate of fire meant that, even with 15%, hit chance they were still going to get a decent DPS.

In Dawn of War 2

Stormtroopers are DoW 2's equivalent of DOW's Kasrkin, they appear in all games but only become widely playable during Retribution, where the Guard becomes a playable faction. You only fight alongside them in the original DoW 2 and you get to control two squads of them on one mission during Chaos Rising. They use Hot-Shot lasguns with armor-piercing effects. Stormtroopers can be upgraded with multiple "kits" that lets them be more effective to different targets and fit certain circumstances.

The kits are:

• Assault kit, which increases their fire rate and range, but now actually costs something and makes them take more damage as well (Outdated as of version 3.18, more info on the Retribution wiki comments). Usually passed up in favour of melta, but still useful for dealing with some elite infantry and commanders.
• Anti-tank kit, which easily makes them the best hunter-killer unit the Imperial Guard have available in the game. Their melta guns and melta bombs allow them to wreck vehicles, fuck up enemy power supplies, and to a lesser extent, tear up enemy commanders and superheavies.

Unlike their original appearance in DoW, stormtroopers this time round actually have a role other than being guardsman squad 2.0. Their weapon options and ability to infiltrate make them ideal for removing high priority targets like enemy vehicles, elite units, or commanders. They can also be used to disrupt power supplies and decap points. Although stormtroopers are a bit tougher and have more dakka than regular guardsmen, their unit size is much smaller (compare 5 troopers to an infantry squad's maximum of 12) and they fare even worse in melee. With the addition of a sergeant and commissar, guardsman infantry squads can reinforce three troopers at a time for a fraction of the cost of a stormtrooper, which makes them a whole lot more resilient in the field when combined with a reinforcement point such as a Chimera.

In Last Stand the Stormtroopers are an available command accessory for the Lord-General, allowing him to call down a squad of them at any time in order to assist. While this gives a major reduction in energy expenditure via their passive and offer the only mobility boost available, they are pretty much dead last in terms of utility. You get only a small few of them - they aren't tanky like ogryns, they aren't very good in close quarters like the catachans and they can't take any other weapons like the guardsmen.

On Tabletop

What they look like.

Scions/Stormtroopers are difficult to classify in tabletop. Many players eschew them, since the Imperial Guard used to be able to field cheaper Infiltrators with carapace armor (and better range as part of the bargain) via Veteran Squads, and Veterans had Objective Secured as part of the bargain (but now so do Scions, who can be taken as Troops). On the other hand, Scions Deep Strike by default and come with AP-2 weapons which can put the hurt on just about anything, including Marines.

As of 8th Scions have effectively replaced Veterans as an up-armored, elite Troops choice. Although Veterans can still take heavy weapon teams and heavy flamers (which makes them a better choice for a static gunline) they have lost infiltrate and their old doctrines (carapace armor, camo-cloaks, snare mines), making them worth just about fuck-all to anyone who isn't running a Vanguard.

Where Scions come into their own, however, is as surgical strike units. Suffice to say, Scions are amazing units when used for target elimination - nobody likes taking AP-2 fire from anything (except, you know, TEQ) and they provide easy deep-striking plasma and meltas that the Imperial Guard lacks. Scions are a comparatively mobile and deadly force whose basic guns now have better AP than a goddamn bolter. Access to up to 4x special weapons and BS+3 doesn't hurt either - well, unless you're the enemy. Then it actually does hurt. A lot.

Scions can take a transport such as a Chimera or Taurox Prime, however, Valkries and Vendettas are much more reliable than simply deep striking. In 8th they can also be taken as their own stand-alone regiment and come with interesting stratagems and special rules. For instance, their Warlords can Deny the Witch as if they were a psyker; with Superior Intelligence you can shoot at deep strikers within 12" the instant they arrive; combine the Tactical Auto-Reliquary of Tiberius with Master of Command and your Tempestor Prime becomes a 40 pt Creed; and if your Stormies are in double-tap range then their weapons gets an extra shot whenever you roll 6+ to hit.

A common joke amongst /tg/ is that in order to win, you must spam MOAR STORMTROOPERS.

9th Edition seems to have taken a surprising turn as they announced the return of the Kasrkin, implying that they'll either be a legitimate unit to include in a Cadian army or as some reskins.

Tales of Hilarity

Almost every 40K oldfag can tell you a tale of their first (and often most memorable) encounter with Stormtroopers; usually it pans out around the same way: the player (often playing something lighter-armored, like Tyranids, Orks, or Eldar) has fought a lot of Guard units, but hasn't really seen Stormtroopers in action before, and the Storms are usually camping an objective or getting ready to clear an area. The unwitting player moves in to intercept, expecting just another Guardsman squad, and proceeds to learn that Carapace Armor is a thing and it makes its wearer substantially harder to kill than Guardsmen are. The Stormtroopers then immediately return fire and quickly mulch the squad with their BS4 and AP3 Hellguns (AP5 in the previous editions, but with 24" range) weapons, and the young player quickly learns to never take a unit lightly again.

Another humorous tale that is constantly related regarding Stormtroopers is when Inquisitorial Stormtrooper Sergeants, in 3rd edition, were able to, due to a typo in earlier prints of the codex, take Thunder Hammers. This was expensive, but since a standard power weapon was only 10 less, this quickly became a thing wherein a Stormtrooper squad could be an effective charge deterrent, as enemies would assault the squad, the Stormtroopers would armor save most of the damage, and the hits from the Thunder Hammer would screw the attacker's initiative, resulting in the one thing every close-combat squad fears: Losing an assault to a bunch of Squishy humies. This was errata'd away in later editions, though there was an article on Games-Workshop's website condoning the practice back in 2006.

Star Wars

Note the substantial height differences in a group that's supposedly a bunch of clones. There's a reason the EU didn't go with the idea that all Stormtroopers are clones. At least not clones of the same person.

In Star Wars Stormtroopers are the iconic white armored soldiers of the Galactic Empire. They were formed out of the remaining clones of the Grand Army of the Republic when it was dissolved into the Empire. The increase in numbers needed to hold territory instead of just take it combined with a clone rebellion and exhaustion of the original Jango Fett DNA has seen the Empire transition away from a force exclusively made up of clones. As a result, rather than be children of a single clone daddy, Stormtroopers are made up of recruited humans as well as clones of newer templates created by Spaarti cloning, a process that produced much faster results than the Kaminoan cloning used by the original clones at the cost of lower quality. Their fancy armor isn't very good against blasters, even within the films.

Clones? Skill Level?

Lucas has waffled on if Stormtroopers are cloned or not. The original films had large groups of uneven height stand next to each other and in his early notes for Expanded Universe material, he stated there were female Stormtroopers at other duty stations. Later on he made edits in the special edition and other rereleases, plus a gag in the prequels that the Stromtrooper hitting his head was inherited from Jango, that implied they were. Stormtroopers are also said to be elite soldiers with peerless marksmanship ("Only Imperial Stormtroopers are so precise."). Despite this, their poor showing during the Death Star escape (people often forget they were intentionally letting them get away to track them) and the Battle of Endor (for which there is no excuse) and minimal appearance of "normal" Imperial soldiers (The Holiday Special and SOLO: A Star Wars story are the only places in live action where they're anything but background details) have resulted in the expanded universe and most RPGs showing them as disposable mooks. But the fact is, Stormtroopers remain a separate institution within the Imperial military, kind of like the Waffen-SS or Napoleons Imperial Guard, with their own resources and command structures separated from the rest of it.

The actual rank-and-file in the Imperial military is the aptly named Imperial Army which sees very little representation in any Star Wars media and many writers completely forget about, at least until recently. The brief occasions where the Army is represented in any capacity are the AT-ST pilots in Episode 6 and the poor schmucks slaughtered by the dozens in the awesome-as-heck Battle of Mimban in Solo. Apparently, Army troopers are mainly defensive garrisons and PDF forces, and they're not very willing to carry out the Empire's more dubious orders, which is why they tend not to be featured in the major climactic events shown in most media. But again, most people, fans and writers alike, forget about this detail, and so Stormtroopers are made the primary infantry force in the franchise, even when it doesn't make sense for a supposedly elite force being used to garrison some no-name outpost. And consequentially, often portrayed as the lowly fodder. This was eventually rectified by establishing that while Vader's personal 501st Legion, the only ones Kenobi was familiar with (besides his own unit from the Clone Wars, the 212 under Cody, and other GAR units who obviously are better than conscript masses due to combat experience), were indeed cloned elites and the only unit to fully retain the Jango Fett template due to them being fanatically loyal, the majority of Stormtroopers in the galaxy are merely recruited humans with much lower standards or cloned from younger, inferior, clone daddies. The Commando Clones were also brought into the 501 and the rest of the Fett clones either retired early due to accelerated aging, defected to Mandalore through Kal Skirata or gave training to others like Cody and then retired after a few years of that. The 501st had their moment of glory at Hoth as the main infantry force accompanying Vader, but even then between the loss of several AT-ATs to Luke, Wedge and the other Rogue Squadron pilots and to the ice breaking under some of the others and the accelerated aging reducing performance, it was a tactical win but a strategic failure as many rebels managed to escape. The 501st Legion Fett clones were then retired in the next year before Endor due to the aging problems with clones and degradation in the original DNA sample, which helps explain their losses there. Thrawn later rebuilt the 501st with elite recruits and this version of the unit continues for more than a century with the best of the best being placed there, transferring from Thrawn to the Imperial Remnant at Bastion and serving until the end of Legends history.

Another phenomena in the expanded universe is attempts to explain the poor accuracy with gear issues. These range from poor vision in helmets to defective components in blasters. These two could be used together, saying that the armor was designed for a very limited size range (a literal bunch of clones) and fit poorly on recruited soldiers. This is especially so when it's outright canon that early generation clone armor was made by non-humans and did indeed impede movement. However it is also worth pointing out that in the real world 90% of the shots a soldier takes will miss anyway.

Where Stormtroopers do excel consistently is in fights against equally nameless foes. All RPGs stats and asymmetrical video games show Stormtroopers are flat out better than the typical Rebel soldier, B1 droid or Hutt thug. This isn't so curbstompingly better that Stormtroopers would win with 2-1 odds without better tactics (which they'd have in narrative but isn't represented mechanically) but they do have better stats. Officially they're just worse than any hero. If you watch the original Star Wars movie (whether remastered or not), the Stormtroopers whenever fighting non-plot armored people absolutely curbstomp. Like in the first scene of the movie when they go through a single-file door into a heavily defended and narrow corridor and yet slaughter the absolute fuck out of the Rebels. In fact, the only time we see them faring badly in firefights in the movies is on the Death Star in the first movie (when there was a beacon on the Falcon and so their misses were likely due to orders to let the heroes escape), against Luke on Cloud City in The Empire Strikes Back (he's a freaking Force-sensitive with some training and combat experience, oh and also the son of the literal Chosen One of the setting, so that isn't a fair measurement), and we don't really see anything in Return of the Jedi due to Ewok shenanigans. When the Millennium Falcon was escaping Tatooine where the troopers were arguably trying to damage the ship's engines and not actively trying to shoot Han Solo. With the Imperial Remnant they show competence fighting at the Yuuzhan Vong War and continue service until the end of the known timeline, even fighting on both sides of the last known war and one company takes part in the last battle known, witnessing the extinction of the Sith.

Within the Disney canon, Rogue One also indicates another factor in which Force Adept Chirrut Imwe walks out of cover (after a Rebel Soldier gets wasted by Stormtroopers for being exposed from cover for a second) and walks through a hail of blaster fire sedately while chanting a matra to the Force. This indicates that the Force is to some degree actively intervening for force sensitive individuals by making shots run astray, though even this is not a 100% fool proof solution as he was eventually gunned down.

Variants

Since the Empire is large and includes every biome known to man and several fictional ones (and the Star Wars franchise is built on toy sales), the Stormtrooper Corps has specialized units for nearly everything imaginable. On top of this, there have also been many attempts to create even better versions of normal Stormtroopers, leading to quite a few different "elite" types that almost all wear black armor. This is a list of all the ones people care about because they are common, cool, or appeared in a movie or a good EU product, plus a few memorable one-offs.

• Coastal Defender Stormtrooper: Also known by the less intimidating name of "Shore Troopers". Made for Rogue One, they basically get stationed on beaches and other tropical places like Scariff, where the movie's big battle takes place. In theory, this should mean they get the best jobs of any Stormtrooper, but as Rogue One and The Mandalorian both show, this isn't really the case.
• Cold assault stormtrooper: More commonly known as snowtroopers, this is a normal group of Stormtroopers outfited with cold weather gear. Most infamous for their appearance at the Battle of Hoth, but they've seen many other frozen battlefields. One of the few non-standard variants seen on film.
• Dark Trooper: A series of battle droids (and cybernetically augmented soldiers depending on iteration), with the later models also doubling as Power Armor that can be worn by a regular Stormtrooper. Discontinued after Kyle Katarn blew up their mobile production facility, taking the project notes and designer with it, in Dark Forces. Brought into Disney's canon in season 2 of The Mandalorian to the sound of questionable dubstep, but the Mouse House did remember to keep them dangerous...until Luke Skywalker shows up that is.
  • Purge Trooper: A variant Dark Trooper in Legends designed to hunt down Force-users like surviving Jedi, making them basically the Sentinels to the Jedi's X-Men. Made for The Force Unleashed, where they are easily one of the most annoying enemies in the game. Disney has their own Purge Troopers, but there they're Clone Troopers in black Paratrooper armor with some red instead of OP droids, and can be heard enjoying combat a little too much in Star Wars Jedi: Fallen Order.
• Death Trooper: One of two Stormtrooper variants of note introduced in Rogue One, they basically function as Disney's equivalent to Shadow Stormtroopers: black armored elites who are more stealthy than regular...even though Shadow Stormtroopers still exist also. For some reason their helmets garble their voices into sinister-sounding but completely incoherent gibberish, ensuring they'd be useless at any drive-thru (as more than one person online has already pointed out).
• Desert Stormtrooper: More commonly known as sandtroopers. Made for hot environments like Tatooine, making them the very first Stormtrooper variant ever shown. They all wear backpacks and an orange or black shoulder pad, the latter also sometimes showing up on regular Stormtroopers who are officers or heavy weapons specialists (it's a bit inconsistent).
• Emperor's Royal Guard: Stormtroopers trained to protect Emperor Palpatine himself. Their members are drawn from the ranks of the best Stormtrooper forces, then put through exceptionally brutal training on a barren desert hellhole which only the best survive, turning them into functional supersoldiers, a premise you definitely haven't seen before. They're then put under the direct command of Palpatine, with orders to protect him and undertake any sabotage/assassination/frontline combat missions he commands them to. They mainly use force pikes (shock sticks basically), or double-bladed vibroswords to stab and slash things to death in the Emperor's name, though they can and do use red-tinted versions of Stormtrooper armour and vehicles when in the field. While obviously not able to take down Luke Skywalker-types, they are still among the best non Force Users in the setting. In Legends, Royal Guards also have a secondary function of keeping an eye on Vader, reporting on his every activity so that Vader doesn't have an opportunity to betray Palpatine; they may not be a match for him, but Vader can hardly do anything without the Emperor knowing about it.
  • Coruscant Guard: Another red-armored elite branch of the Empire, they're basically Coruscant's brutal, no-nonsense police force. Mostly showed up in Shadows of the Empire, where Luke disguising himself as one allowed them to (sort of), get an action figure.
  • Riot Trooper: Made exclusively for Force Unleashed II. They are also trained on Yinchorr, but wear white armor and are seemingly more common and less skilled than the red-robed Royal Guards. Use electro-staves like the ones wielded by Grievous' Magnaguards.
  • Shadow Guard: Black armored, Force-sensitive versions of the Royal Guard. They use red-bladed lightsaber pikes and Force powers in combat, acting as Palpatine's elite enforcers and assassins. Exactly where they come from is a complete mystery, with even Vader kept in the dark on their origins - in-universe theories range from them being Jedi Knights captured, tortured, and mind-broken by the Empire until they're little more than speechless living weapons to them being Force-sensitives promoted from the rank of the regular Royal Guard. Of course, these explanations are hardly mutually exclusive.
  • Praetorian Guards: Before they became the bodyguards of Snoke and the stars of one of the most contentious fight scenes in a Star Wars movie, Season 3 of the Mandalorian reveals that the Praetorians were already active as part of the Imperial Remnant. Armor is possibly Beskar.
• EVO Trooper: Short for "environmental". Debuting in The Force Unleashed, they're sent to particularly exotic and dangerous locales where its felt a more specialized trooper is needed (because the Empire never has enough of those). Wield a rifle that looks a bit like a miniature chaingun, and are said to be selected from the ranks of Stormtroopers with particularly pronounced hatred of non-humans.
  • Shadow EVO Trooper: Variant of the variant; Shadow Stormtroopers with experimental version of the EVO armor that can go invisible like Shadow Stormtrooper armor.
• Hazard Troopers: The Empire's Space Marines. Having super-bulky armor and as such much tankier than other varieties, they are sent on planets with extremely hostile conditions (like acid rain, lava lakes, and so on). Made their first and only appearance in Jedi Academy, where they're more or less the toughest recurring enemy in the game that doesn't have a lightsaber.
• Imperial Armored Commando: Introduced Star Wars Rebels but first shown as live action in Season 3 of The Mandalorian, they're Stormtroopers outfitted with jetpacks, beskar armor, and all the other Mandalorian goodies to basically serve as Imperial Mandalorians (something the Empire had previously before they went and genocided them).
• Incinerator Trooper: Another type introduced in The Force Unleashed, identifiable by their red markings and shoulder pauldron. Their thing is, naturally, being the flamethrower guys. Made it into Disney's canon thanks to showing up in The Mandalorian (does make one wonder why the Empire didn't use them on Endor though, given that's an environment they would have been ideal for).
• Jump Trooper: AKA Rocket Trooper, Sky Trooper and Air Assault Trooper. Stormtroopers with jetpacks. Originally only suitable for short jumps, by the New Republic era the technology has evolved enough for them to get proper jetpacks that let them fly indefinitely.
• Magma Stormtrooper: Also called "Lavatroopers" in the old Legends Canon, which also gives them the more distinct design of red Stormtrooper armor. In Disney (where to date they've only really appeared in DICE's first Battlefront game), they basically just look exactly the same as Sandtroopers.
• Novatrooper: Oh look, another black-armored variant, though these ones are only a bit better trained than standard Stormtroopers and have similar equipment. Have a bit of gold to balance out all the black, and appear only in the Star Wars: Galaxies MMO. Generally meant to be ceremonial rather than front-line infantry, which may explain why they're not that much better trained.
• Scout Trooper: Scouts, obviously (also snipers according to a bunch of the video games). Scout troopers have a distinct helmet that allows for greater visibility as well as lighter leg and shoulder armor for greater mobility. They typically use Speederbikes and long ranged rifles. Scout troopers are the only type of Stormtrooper besides Mimban Stormtroopers known to even occasionally make use of camouflage (though the ones at Endor did not). One of the few variants shown on film.
  • Star Wars Jedi: Fallen Order and its sequel gives us variants of the variant in the form of Scout Troopers who carry electric batons and are basically the low-level melee enemy. Sequel adds shielded ones.
• Range Trooper: Debuted in Solo (since nary a new OT-Era Star Wars product comes out without introducing at least one new Stormtrooper variant). Have big magnetized boots that let them stick to trains (yes, seriously). Not entirely clear what their specialized role is (beyond selling more toys of course). They also wear fur with their armor and are considered some of the toughest in the Empire.
• Shadow Stormtrooper: Also known as "Shadowtroopers" and "Blackhole Stormtroopers", they're your standard Stormtroopers, but their armor is black. Depending on the writer, this is either just for show, or means they have stealth capabilities and are a cut above standard Stormtroopers. Exist in Disney as well as Legends, even though the Death Troopers make them somewhat redundant in the former.
  • Shadowtrooper: No, your eyes aren't deceiving you. There is another, unrelated type of black-armored elite Imperial called "Shadowtrooper". These ones are only in Legends, and are Stormtroopers forcibly made Force-Sensitive, outfitted with cortosis armor that can take multiple hits from a lightsaber, and used by the Imperial Remnant against the Jedi of Luke's Order. Kyle Katarn fights them in Jedi Outcast.
• Storm Commandos: Looking very similar to Scout Troopers, but in black. So aesthetically to Scout Troopers what Shadow Stormtroopers are to regular Stormtroopers. One of many black-armored elites the Empire use, but they don't get much exposure in either Legends or Disney (despite existing in both). General Crix Madine used to lead them before joining the Rebels.
• Stormtrooper Commander: Exactly what it sounds like. Only really a unique variant in The Force Unleashed, where they're differentiated from standard Stormtroopers with blue markings intended to evoke the ARC Troopers (as they were meant to be a spiritual successor to them), and personal force-fields. Whenever Stormtrooper officers and squad leaders show up anywhere else, they usually just get orange shoulder pads instead of the blue markings.
• Terror Trooper: Introduced in The Force Unleashed II, they're an experimental Stormtrooper type recognizable by their sharp claws, skull-like masks, and the fact that they're merciless, bloodthirsty killers. Their masks are clearly based off of General Grievous' mask.
• Wet Weather Gear stormtrooper: Also called "Mimban Stormtroopers" because their only big appearance so far is on Mimban in the Han Solo movie. Armor has a light gray camo pattern, and they get capes. Presumably meant for rainy and muddy environments (so basically the ones who go to shitty weather planets).
• Wetland assault stormtrooper: More commonly known as swamptroopers, this branch wears green colored gear optimized for swamps. Fairly obscure, mostly making appearances in Jedi Outcast and Galaxies and that's it.
• Zero-G assault stormtrooper: More commonly known as spacetroopers, this branch wears Power Armor designed for boarding and capturing disabled ships. They are first mentioned in Star Wars RPG materials by West End Games, but are most famous for their appearance in the climax of Heir to the Empire, the first book of the Thrawn trilogy. There is a pair of Stormtroopers with an unusual backpack (possibly a jetpack) that are very briefly seen in the original movie, but they look nothing like future deceptions of spacetroopers, fanoned as that configuration being more for guys patrolling out of atmosphere but in gravity. They also appear in the computer game X-Wing: Alliance.
• Mortar Stormtroopers: One of these made a brief appearance in Season 2 of the Mandalorian. Considering the writers and directors own known nerdhood into star wars, they were most likely made for the scene as parody on all the types and variants of the stormtroopers.

OK, I think we got them all. If not, you can always check the Wookiepedia page, OG is pretty extensive.