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

===Dominus Knights===
The "biggest" Knights yet (discounting the walking box that is the Porphyrion, and the ceratus chassis. GW calls it a big knight, but it isn't that much bigger than the classic knight chassis), with 28 wounds each, the usual strength and toughness of 8, a 3+/5++ and packed full of guns. But unlike the Questoris Knights these are only WS 4+ so they won't handle close combat so well. Be warned those are '''NOT''' multikit, i.e. you can't magnetize the weapons and get Castellan and Valiant from the same box. FUCK.

Both knights have twin-linked melta turrets and 3 hardpoints, each of which can be equipped with either a turret with 48" Heavy 2D3 S7 AP-1 D3 Siegebreaker Cannons, or a pair of one-shot, one-per-turn 48" Heavy 1 S10 AP-4 D1d6 Shieldbreaker Missiles that ignore Invulnerable Saves.  Note that you have to take two of one, and one of the other.  If you have the points, always take the Cannons - ignoring invuln saves is fun, but unreliable.
*Shieldbreaker missiles seem weak at first, but the Oathbreaker guidance stratagem is 3cp for a reason. Because of their AP, they technically ignore both invul and armour saves, making them absurdly good for sniping characters, especially those with 6 or less wounds. This player can confirm that even named characters (for example, Eldrad) can die to a single missile fired turn one.
*However, the flipside is, you can still only fire one per turn. If you can afford it, make sure you think hard about whether you'd rather have the option for a 3rd missile on turn three (when, odds are, either your knight is dead or you've already won) or if you'd rather fire the extra cannons while he's still alive.

Seriously consider giving these guys the 'Ion Bulwark' warlord trait.  'Rotate Ion Shields' costs 3CP on them and they ''will'' attract a lot of fire.

*'''Dominus Knight Castellan''': Comes with a 48" Heavy 2D6 S7 AP-3 D1 Plasma Decimator (S8 AP-3 D2 if you Overload, but it suffers a mortal wound for every roll of 1 to-hit, so a way to re-roll 1s and/or access to a repair mechanic is a wise choice) and an 80" Heavy D6 S14 AP-5 D3d3 Volcano Lance that lets you re-roll to wound when targeting {{W40kKeyword|TITANIC}} units.  This is GW's answer to FW's Atrapos.  While not quite as good against other superheavies, it's a superb vehicle killer.  Fire at a Guard tankline and watch it evaporate. The QUESTOR MECHANICUS Household Tradition is the only way to get access to the Cawl's Wrath relic. An upgraded Plasma Decimator. Giving you two reasons to always have a Castellan in your army. 
**Super Heavy Auxiliary detachment, Exalted Court (-1Cp), Extra Relic (-1CP), House Raven > Castellan Knight with Cawl's Wrath and Ion bulwark.   
***This gives you a T8 3++ 28W non degrading statline (1CP stratagem), the firepower of roughly 6-7 leman russ but rerolling 1's to hit and to wound, at 60% of the cost. Only downside is that it's CP hungry : bring a guard brigade. This thing has been dominating the meta since the knight release codex, and FAQ/Chapter approved only nerfed it's counters, making it even stronger by contrast.  
***'''Spring 2019 FAQ Update''': [[Meme|WELL WELL, IT'S THE BIG NERF!]] Rotate Ion Shields got nerfed, meaning every Knights' Ion shield can only max out at 4++ and it got a 100 point increase thanks to the Volcano Lance and Plasma Decimator getting sharp point increases, this is easily enough to put the Castellan out of the meta although by no means makes it unplayable, it's range and high damage output is still ridiculous it's just not game breaking like it was before.
*'''Dominus Knight Valiant''': The short range version of the Castellan, trades the powerful long range firepower for RIDICULOUSLY lethal short range guns (plus the twin meltas and same hardpoint weapons options as above). It sports the Flamer-type 18" Heavy 3D6 S7 AP-2 D2 Conflagration Cannon and the 12" Heavy 1 S16 AP-6 D10 (Yes, you read that right - and its real damage output is even higher!) Thundercoil Harpoon. The harpoon also re-rolls to hit against {{W40kKeyword|VEHICLES}} and {{W40kKeyword|MONSTERS}}, and deals an extra D3 Mortal Wounds to the target unit if it deals any damage, making the D10 an ''underestimate'' of its damage.  Try and avoid firing against things with invuln saves.
**The biggest weakness of this guy is that he needs to get in close to do damage, but has the slowest movement of all Knights.  Assume you won't be able to fire the big guns for the first couple of turns, and position to break line of sight. This can't be stressed enough. If you are up against a cc army, the valiant is great, because no one wants to get close, but against a gunline, that's a lot of turns of wasted potential.
**Be careful when going up against Necrons, as the QUANTUM SHIELDING rule makes vehicles that have it literally immune to any damage from the Harpoon.
**A Hawkshroud knight valiant can provide fantastic protection for imperial allies, for 2cp it can fire it's overwatch including that auto-hitting conflagration cannon at a charging enemy unit, this is a potentially game winning strategy particularly if your opponent is caught off-guard.