Editing Warhammer 40,000/8th Edition Tactics/Imperial Knights (section)

===Arm Weapons===
====Auto Weapons====
*'''Rapid-Fire Battle Cannon''': The battle cannon is no longer the reliable MEQ-slayer it once was. While it does have massive 72" range, if you're sitting back and sniping you're not really getting the best out of your knight. Overall, excels at very little (it has a marginal advantage over the other weapons against T7 vehicles due to the wound math).
**Take one if you want more dakka on the Crusader, and it's still okay at dealing with medium vehicles, just don't expect it to be as good as it was in 7th.
**With {{W40Kkeyword|House Raven}} the RFBC has an effective range of 87" (with no movement penalties), easily capable of hitting anything ''anywhere'' on the board. 
**A good tactic would be to fire the RFBC last; 72" is long enough to reach almost anywhere on the board and it's pretty difficult to hide from a Knight. If your dice get cold and your other knights leave some stragglers, you can use the cannon(s) to clean up.
**Don't underestimate the battle cannon in 8th. It's combination of multiple shots, S8, decent AP (-2) and multiple damage (Dd3) means that it will perform reliably, if not spectacularly, against just about everything in the game. 
*'''Armiger Autocannon''': Unique to the Armiger Helverin, 60" Heavy 2D3, S7, AP-1, 3 damage. In addition, the weapon ignores the penalty for moving and shooting heavy weapons. It will have difficulty against the T8 fatties (Land Raiders, Leman Russ', Wraithknights) and 3+ saves mean quantity is vital, but the Helverin mounts two of them. Fantastic for how cheap a platform it is mounted on, it will do work for you.
**The most efficient weapon you have for taking out Guilliman; you hit and wound on 3+ with 4d3 attacks, the AP knocks him down to a 3+ save, and damage 3 means he'll go down quick. All of this means that you “only” need 20.25 shots from this gun to take him down, and for Guillimans price you can buy two Armigers which can pump out an average of 16 of these shots a turn (although this doesn’t take into account his regeneration ability or the fact he’ll be hiding behind meat shields).
*'''Avenger Gatling Cannon''':The best all-rounder, and now cheaper than the RFBC even after including the mandatory heavy flamer! 12 S6/AP-2/D2 is the absolute champ against all kinds of infantry, including TEQ (that 2 damage in particular will make Primaris marines and the like cry). Tears up light vehicles and can do useful work against the heavy stuff - out-shooting the RFBC even if it doesn't match the Inferno cannon.
**Always a good idea to pair with a Thermal Cannon on a Crusader Knight, as they share the same range and complement each other pretty well.

====Meltas and Flamers====
*'''Thermal Cannon''': What melta guns dream of being when they grow up. This is your heavy armour hunter, and now doing D6 shots to all targets thanks to a change in the new AdMech codex it far excels the other weapons in a vehicle-hunting role. The number of shots is a good candidate for a CP re-roll. Also, the cheapest of the three big guns by almost 30 points. Surprisingly though, not your best choice against TEQ - it really needs to be targeting multi-wound models to make it count (Terminators have 2 wounds, so the Avenger Gatling Cannon wins out).
**When you consider that Knights don't take movement penalties on heavy weapons (and can advance + shoot with no penalty if {{W40Kkeyword|House Raven}}) the range on a Thermal cannon goes from 36" to a pretty respectable 49" to 54" (ave of 51"). Also, while the RFB gets double the number of shots it's really outclassed by the Avenger Gatling Cannon, and the Thermal Cannon hits harder (+1S, +1AP, x2 damage) AND costs less.
*'''Thermal Spear''': The Thermal Cannon's lesser cousin carried by the Armiger Warglaive. 30" Assault D3 S8 Ap-4 D6 damage.
**Considering Armigers have a movement of 14", the range on these is more like 44", which makes them really good.
*'''Conflagration Cannon''': The middle child between a Titan Inferno Gun and a Hellhound's Inferno Cannon. 18" Heavy 3d6 with S7 AP-2 2 D as well as the auto-hitting goodness of a flame weapon. At full movement this gives your Knight a surprisingly scary 28" threat range.
**''Blessed by the Sacristans'' (Warlord Trait) vs ''Traitor's Pyre'' (Relic): Mathhammer shows that with ''Blessed by the Sacristans'' this weapon will chew GEQs, MEQs, and even TEQs with 3++. The ''Traitor's Pyre'', on the other hand, excels against {{W40Kkeyword|Vehicle}} and {{W40Kkeyword|Monster}} units.

====Plasma Weapons====
*'''Plasma Decimator''': The Castellan's first arm weapon. 48", Heavy 2d6, S7/8, AP-3, 1/2 D. Like most plasma weapons, it can be overcharged for the boosted S and D, but it'll take a mortal wound for each hit roll of 1 it makes. 
** Range aside this is basically a Leman Russ Executioner Cannon on a sturdier platform. It's not ''bad'' per se, until you consider that Guard players can bring '''4''' of these bad motherfuckers for the same price and it suffers the same problem every plasma weapon has on a platform with a degrading staline, in that its low power version is underpowered compared to what else you can take, while overpowering isn't worthwhile unless you can re-roll ones (hint: {{W40Kkeyword|House Vulker}} lets you do exactly that). 
**Counter opinion: yes this gun is pretty average. But when overcharging you really only have to worry about 1-3 mortal wounds. Which is not ideal of course, but on a model with so many wounds, it sort of does take a bit of the danger out of it (hint: {{W40Kkeyword|House Hawkshroud}} is useful for this).
**House Raven players using their house command benefit "order of companions" to re-roll all 1s, letting you overcharge this (and by this i mean replace the plasma decimator with the cawls wrath relic) and do 3 damage a shot with a little chance to self damage.
**After a bit of experience with this weapon, it actually isn't that bad. It's like a more specialised version of the rfbc. Excels at murdering elite infantry, and whilst it does seem pretty lackluster, in reality if you are firing at the right target (elite infantry with only one or two wounds) 2d6 shots can really fucking hurt.
**Went up 40 points in the 2019 Big FAQ. This combined with the Volcano lance's increase makes the Knight Castellan <s>roughly</s> <span style='color:blue;'>literally exactly</span> 100 points more expensive than it used to be.

====Las Weapons====
*'''Volcano Lance''': The Castellan's other arm weapon. Basically a smaller [[Volcano Cannon]], with slightly less range and Strength than its Shadowsword-mounted cousin. But a 80" Heavy d6 S14 AP-5 3d3 D gun that rerolls failed wounds against {{W40Kkeyword|Titanic}} units is still nothing to sneeze at. Went up to 60 points as of the 2019 Spring FAQ.
*'''Las Impulsor''': The new weapon carried by Canis Rex and the Knight Preceptor. Essentially a laser shotgun. Has two firing modes. 36" heavy 2d6, S 6, Ap -2, d3 damage or 18" heavy d6, S 12, ap -4, d6 damage. 
** This perfectly supports both the long-range anti-infantry Helverin and the short-range anti-tank Warglaive, while still being able to mix it up if an enemy slips through.
** This is the jack of all trades option, with the inevitable "master of none" downside. 2-12 avenger cannon shots, but not guaranteed to get 2D, or a shorter-ranged thermal cannon with enough strength to wound T6 enemies on a 2+. On the other hand, it's never going to be wasted on inappropriate targets and the d3 damage on the Dispersed mode gives it a little extra usefulness against 3-wound models like Grey Knight Paladins.

====Other====
*'''Thundercoil Harpoon''': MAN THE HARPOONS! But seriously, this thing is a monster. 12" of range means you'll need to be right in your opponent's face to use it and it only has 1 shot, but with S16 AP-6 D10 '''and''' rerolling failed hits against {{W40Kkeyword|Vehicles}} and {{W40Kkeyword|Monsters}} '''''and up to d3 extra mortal wounds''''' for good measure, that one shot will fuck up almost anything it doesn't just kill outright.
** Given that you'll only get one or two shots with this thing over the course an entire game you need to beware of anything that can screw with your BS (hit modifiers, damage tables, etc). Also anything with an invulnerable save (like, say, another Knight) can still try to use that. Overall, the Thundercoil Harpoon is a "fun" option and is best suited for:
*** Stuff with lots of wounds but no invulnerable saves, like Baneblades, Land Raiders, Tyranid monsters of all types, and Gorkanauts
*** Dealing the final fuck you to said stuff when they are at 11 wounds or less (10D + d3 mortal wounds)
** Hilariously, Quantum Shielding makes Necrons ''completely immune'' to this weapon, as they'll autopass their roll against a 10D weapon.
*** Except for their Monoliths and spearing that thing is automatically taking it down to below half wounds.

====Close Combat====
These guys have lost the big "D", and in exchange do a flat 6 damage per hit. Great at wrecking vehicles and MCs, but they can be very binary - there's lots of things like Dreadnoughts with >6 wounds that take two hits to kill and can leave a nasty mark if they get to hit back, so it's always advisable to try to soften these targets up a bit first. As noted above, you're better off kicking most infantry to death instead.
*'''Reaper Chainsword''': S+6 (14)/AP-3/D6. Best for light-medium vehicles and medium-sized gribblies. It's not bad against stuff like Land Raiders, but the gauntlet edges it out.
**'''Chain-Cleaver''': Has two attack options: Strike and Sweep. Strike is Sx2/AP-3/3D and Sweep S-/AP-2/1D but doubles the amount of hit rolls you can make with it. So this gives the Armiger some very nice added adaptability in their close combat.
*'''Thunderstrike Gauntlet''': S16/AP-4/D6. Higher strength and AP in exchange for -1 to hit and a meager +5 points. This excels at pretty much the same things the Inferno Cannon does; anything T7/3+ or better. Plus, you get the lulzy spectacle of chucking a dead Razorback at his warlord for extra mortal wounds. The choice between the two is pretty much a toss-up depending on your opponent - take the gauntlet vs. IG and the sword vs. Deldar, etc, but either one will do the job most of the time.
**The gauntlet gives you access to the Death Grip stratagem, which is a death sentence for any infantry warlord. Sure, he was probably already dead if you got into melee with him in the first place, but this is faster...and ''way'' more satisfying.