2x Blister of GK in Power Armor- Question, do you mean the seargeant, because that is the only Grey Knight blister I see that does not have a psycannon or incinerator.
Nope, I mean just normal GK in Power Armor. Like
this. Each box comes with 1 Justicar (the sergeant for the unit), so you have no need to buy more of those yet. But the box comes with only three standard GK, so you'll definitely want a few more.
Also what does the Cherub do strategy wise in help the inquisitor, I also have the same question for the Accolyte, Heirophant, Mystic, Sage, and Servo Skulls. I will most likely be going for a shooty Inquisitor.
There are six types of henchmen:
Acolytes: Can be given the Inquisitor's wounds, can be given wargear & weapons.
Mystics: One allows you to shoot at incoming summoned or deepstruck units. Two allows a nearby unit to do it instead.
Sages: One improves the Inquisitor's BS. two gives one reroll on a shooting test that can be used by anyone in the unit (handy when you have a Plasma Cannon that overheats - you can negate it!).
Familiars: Both cherubs and servo skulls count as Familiars, the difference is only appearance. They increase the Inquisitor's initiative, and 2+ allows the Inquisitor to buy more than one psychic power.
Heirophants: Make it hard for Daemons to charge the Inquisitor's unit, and improves the Inquisitor's Ld (to a max of 10, so this doesn't help Lords).
Warriors: Just what it sounds like. You can choose from: Powerfist, pistol/ccw, flamer, plasma gun, meltagun, grenade launcher, hellgun, plasma cannon, heavy bolter, or multi-melta. They also improve the Inquisitor's WS.
For a shooty Inquisitor Lord, I suggest this:
Lord (Psycannon, Auspex)
2 Servitors with Heavy Bolters
1 Servitor with Plasma Cannon
2-3 Sages
1-2 Mystics
0-3 Acolytes (I'd give them a bolter and nothing else)