Warhammer 40,000: Kill Team (HoR)/Tactics/Grey Knights(7E)

Like in the big game, the Grey Knights are an army that focuses highly on small numbers of elite warriors. Each model comes with a hefty cost, meaning that more often than not you'll be running with a very sturdy force that can easily be outnumbered by the enemy and will more often than not be forced to test for Routing. However, each force is more than capable for testing in anything in Ld with every model having Ld 8/9 (And one model even scoring the motherlode with Ld 10!), meaning that you can fight on despite the losses in most cases.

Rules

• Psychic Conduit: Yes, there is a serious check in place to prevent the Grey Knights from being an army of walking Gorgonzola cheese. This rule essentially makes it that the majority of Grey Knights aren't psykers in a traditional sense, just like the Horrors of Tzeentch. Instead, the moment a model that normally has Psyker dies, a model with this rule instead becomes a Psyker instead and gains Banishment and Hammerhand from the Daemonology (Sanctic) discipline (and Cleansing Flame if the model in question is a Purifier). It can allow for almost every Grey Knight to gain Psychic Powers to compensate for another's loss, meaning that you'll always have the ability to buff yourself up like hell.
• Teleport Assault: This basically says any unit with the Deep Strike rule on their unit entry can Deep Strike as usual. Keep in mind this means the HoR entry, not the codex version. Interceptors lost this rule, but honestly, it doesn't really matter given their ability to shunt. Purifiers still lack this as well to prevent Turn 1 Cleansing Flame nonsense.
• Psychic Brotherhood*: When casting psychic powers, this allows your units to successfully harness Warp Charges on a roll of 3+ instead of the usual 4+. This one is a blessing straight from the Emperor Himself that bestows some welcome reliability to those Hammerhand and Force rolls when you truly need them.

Wargear

• Rad Grenade: Yes, it's back. Models charging/charged by a model who uses this grenade take -1T for the turn, meaning an easier time instakilling if you have Hammerhand in play. Only draw is that it can't stack, and the pricetag it has kinda discourages that anyway.
• Psybolt Ammunition: And just like that, all is right with this codex. Your cheap +1S bonus for all bolt weapons is here. Rejoice, for now those key units can now rely on their bolters to kill things more reliably now.
• Master-Crafted Weapon: It's a Master-Crafted Weapon. Take for a melee weapon or maybe your Storm Bolter.
• Suspensors: These let Heavy Weapons fire on the move at half-range. Only really useful for Psilensers, and that can be a nice grab.
• Anointed Weapon: A cheaper way to ensure that daemons die, this gives your weapon Poisoned (3+) against models with the Daemon USR. Enjoy wrecking them.
• Unguents of Warding: You get a +1 Bonus to Deny. That's right, you get a 3+ with the Nemesis Warding Stave! It's a real cool grab at 5 points.
• Auspex: Another codex marine snag, this can reduce the cover of a model within 12" by -1 at the cost of shooting. Grab for some surprise heavy ordinance.
• Bionics: 6+ FNP. Not a bad grab.
• Targeter: Grants a model re-rolls on 1s if they didn't move. A decent take.

Leaders Only

• Consecrated Scrolls: Thought the Eldar had the only perils-negating rule out there? Not anymore. If your guy ever Perils, you can roll a d6 and on a 5+, you can ignore it. Nice!
• Purity Seal: Your Leader's IP boosts from 6" to 12". Being mostly Ld 8/9, this isn't such an auto-take. Save the points for a more necessary upgrade if you need it.
• Sacred Incense: Chaos Space Marines and models with the Daemon USR take -1I if they're within 3" of the Leader. Being that these models are usually I4 (I5 if aligned with Slaanesh), this can give you an edge in taking down the traitors before taking a hit.

Justicar Only

• Grimoire of True Names: Ohhhh boy is this a cruel choice (especially if you consider that Phil Kelly took it for the Daemons). Models with the Daemon USR that go in base contact with the Justicar halves their WS. This. Will. STING. Against Deamons at least. Everyone else won't care.
• Icon of the Just: Gives your Justicar a 5++ Invul. Don't take it with Terminator armor, but it's a decent idea otherwise.

Paladin Only

• Narthecium: Same as any other codex with FNP for models within 6". Only one Pallie can grab this, and it's expensive enough that it's not such an auto-take.

Terminator Only

• Teleporter: In exchange for assaulting, your termie can jump 2d6". Good for escaping a trap or baiting.

Techmarine Only

• Photon Beam: If you ever want to make a surprise alpha-strike, this can find a way to you. It is a harmless 36" shot, but anything he hits can then be blinded. Blinded means I1. I1 means that you can stomp shit the moment you charge. Take if you feel like the Incense isn't going to cut it/you're not up against Chaos.

FOC

• 1 Leader
• 1-20 Core
• 0-3 Special

Leaders

• Paladin Champion: Starts off The priciest of the Leaders stock, but all his options ultimately end up being weapons or wargear. His big role is being the giant damage sponge, as he starts off with termie armor, and thus can wade through heavy blows like nothing. He also gets Banishment and Hammerhand, which allow him to buff up his units considerably, and if you throw that with a rad grenade, things will always die.
• Justicar: Your utility Leader, with only the basic wargear of a PAGK. Cheapest of them and comes only with access to weapons and wargear, as well as options to become different sorts of leaders...
  • Terminator Justicar: Pretty cheap for 10 points, you can grab terminator armor to make you tougher to break. You're otherwise the same as before.
  • Knight of the Flame: You exchange access to DS for Fearless, Cleansing Flame, and Soulblaze on melee attacks. Pretty nice for a challenge-based leader.
  • Interceptor Justicar: The only one that changes the FOC, this gives you a teleporter and the ability to take more Interceptors.
• Adept: This guy is a power armor Librarian, which is a surprise considering nothing like that exists in the codex. He gets the same weapon options as normal, just now with a 3+. He can use either Banishment (Okay for boosting how to kill daemons), Prescience (For fire support), Flame Breath (To kill mobs), Assail (To trap someone), or Psychic Shriek (More mob management). Most unusual among the other codex Librarians, however, is that for a hefty price, this guy can actually gain ML2 along with his more Librarian-like statline (including the aforementioned Ld 10). Issue with that method is that he'll usually cost you half your points allotment, so only grab the bonus ML if you really need a bonus power (i.e. supporting Banishment and Prescience while a Techie gives Hammerhand). The big weakness to taking the Adept though is that if he dies, nobody inherits his powers. Thus, he usually has to be really well-protected, especially as he's locked to power armor.

Core

• Grey Knight: Your basic Grey Knight with one per five grabbing a special weapon. You'll probably be taking these guys if you want to save up on bigger units with more tools. Especially with an Adept.
• Grey Knight Terminator: Yes, you can take Termies without reservation as Core. One of five can grab a special weapon. You can use these guys if you feel confident in how everyone else is kitted, as these guys a plenty expensive.
• Interceptor: Hardcapped to 0-5 without an Interceptor Justicar. These guys will usually be the alpha-strikers. One per five can grab a special weapon if you feel like grabbing them for shooty so you can trap the enemy in a bigger fire.

Special

• Purifier: Fearless, Soulblaze melee, and a rather nice 2 attacks at I4 makes these guys a decent choice, and if they ever become psykers, they get Banishment, Hammerhand, and Cleansing Flame as powers due to being ML2. One of them can grab a special weapon, though it's usually in good interest to let them lead in combat if you keep your troops for firepower.
• Paladin: These bastards are the most expensive units ever, and for good reason. They're super-buff termies that can fit a couple different roles. One can be used to grab a banner to help lead your teams in assaults and combat, one can grab a Narthecium for FNP, and another can be used to slap bitches silly. Really, they have the utility, but their utility comes at such a high cost that they're bound to be passed up for something cheaper...unless it's the Narthecium.
• Techmarine: Your only non-Leader Psyker in the army with only Hammerhand and Banishment. Otherwise, they'll be basically the same as any other. A suicide unit might be enticing to give another unit their powers, but doing so would seriously cripple you more than either ignoring him or just using him for cover and Hammerhand support.