Thus, what primarily discipline, powers, and feats are best for the Psion? I want to be generally effective and was seriously considering Shaper for crowd control and the occasional damage ability. Astral construct is still useful, even if it's only 1 active at a time. (Build help for the Psion is the primary focus of our discussion.)
This depends a lot on whether you're going to heavily use your believers in combat. If you are (which I'm guessing is the case if you're looking at a DFI bard thrall), Shaper probably isn't the best bet since crowd control would interfere with your believers quite a bit. Instead, I'd actually go Nomad, which is usually fairly situational but is great here: dimension swap
lets you leverage your many believers to move other PCs into melee or get yourself out of danger, psionic levitate
and psionic fly
gets you expendable and highly-mobile scouts, astral caravan
is probably the only way you're going to be able to move all of your believers long distances since teleportation and plane-shifting spells and powers generally allow too few targets, and baleful teleport
deals untyped, hard to resist, Fort-targeting damage which is very effective against "undead lieutenant" types (by which I mean minibosses and horde leaders like vampires, death knights, etc.).
If you're keeping them out of combat, Shaper is good, as is Kineticist, surprisingly: energy missile
and energy current
can clear out your stereotypical undead hordes with Fort-targeting blasting that's also great against lieutenants, control air
is good control with a huge area, and control body
is a poor man's dominate
that works against undead. Also, if Quori Power Link Shards are available (the ones that give you free augmentation a few times a day per shard) that makes Kineticist even more appealing, since using them with energy X
powers is great because (A) they aren't capped like blasting spells are and (B) extra-augmented blasting powers aren't as abusive as save-or-lose powers, rather being on par with moderately-metamagicked blasting spells, so you generally wouldn't piss off the DM or overshadow other party members.
Some general advice, regardless of discipline:
1) Look into the stygian X
powers in CPsi. Stygian bane
turns a group of longbow-wielding believers into a lean mean undead-slaying machine, stygian disruption
is handy if you're forced into melee, stygian dominion
is excellent for short-range scouting and infiltrating groups of undead (and disabling undead lieutenants in a pinch), and stygian erasure
and stygian ward
(via Expanded Knowledge) are helpful against energy-draining undead.
2) Look for powers that target undead weaknesses. Forced share pain
is a double whammy against undead lieutenants--hard to resist with their relatively low Fort and chips away at their relatively low HP (until HD start to inflate at higher levels, of course), and as a bonus it protects against attrition damage from hordes. Energy flash
targets Fort with all energy types (when normally only cold damage does, making energy powers less effective against cold-immune skeletons), and it dazes, which is one condition undead aren't immune to. And so forth.
Also, what build do y'all advise for the main thrall? I was seriously considering Inspire Courage support Bard with Silverbrow Human for Dragonfire Inspiration.
If you're sending believers into combat, this is probably the best pick. Don't forget to give him Requiem to be able to Fascinate and suggest
undead, as well as Undead Bardic Knowledge and Inspire Turning from the Lightbringer bard substitution levels
Alternatively, if you don't have an undead-smiting and/or healing-focused cleric in the party (or perhaps even if you do), an Ardent/Sangehirn
would also be an excellent choice. Ardent, because the Good, Life, and Light and Darkness mantles give a lot of good anti-undead powers, and with Substitute Mantles he can pick up whatever ones they don't already contain. Sangehirn, because it eventually gets fast healing which makes empathic transfer
-based healing during downtime very cost-effective, and his ability to use vigor
on other people can give the entire party a very nice temporary-HP cushion before major fights. And of course having another psionicist as a thrall lets you use metaconcert
, feat leech
, and similar powers on him for higher DCs, more Expanded Knowledges, and so forth.