Given that every single Kill Team can take one or more Librarians, and the Deathwatch are a small, elite force which will likely depend highly on special abilities and force multiplying to be effective on the tabletop, I thought I’d do a quick analysis here on what synergies can be found between the Deathwatch and three of the key Psychic powers available to them:
The standouts here for Deathwatch armies are Endurance and Enfeeble (the various Witchfires and combat buffs to the Librarian are nice, but Deathwatch has enough firepower and close combat damage potential already at the individual model level). Specifically, Endurance gives DW squads FNP(4+), basically doubling their survivability against any attacks S7 or below, which is quite important for the relatively fragile/small-size units they field. Endurance all gives the squad Relentless, which is especially useful for Veteran squads equipped with Grav Guns, Stalker Pattern Bolters, Missile Launchers, etc., allowing them to move and still shoot at full effect, whether foot-slogging, coming out of a Drop Pod/Transport, or using Deep Strike as part of the Black Spear Strike Force. As for Enfeeble, not only does this make the target enemy unit weaker in CC because of -1S, but more significantly it lowers their T by -1 as well. This can be amazing in conjunction with Deathwatch shooting and close combat attacks, lowering the ID threshold by -1 in multiple areas:
1 – S8 meltaguns and inferno pistols can ID Canoptyk Wraiths, TWC, Centurions, Space Marine Biker models, Ork Warbosses, Tau Ghostkeels, DE Grotesques, Nurgle Obliterators, T5 Daemon Princes, Necron Overlords, etc, etc if they have Enfeeble successfully cast on them.
2 – S4 Special Issue Ammunition can ID Eldar/Dark Eldar HQs, Sisters of Battle Characters, Imperial Guardsmen multi-wound models, Skitarii Infantry, Necron Scarabs, Tyranid Ripper Swarms, etc. with Enfeeble cast on them.
3 – S6 Assault Cannons and DW Frag Cannon Templates can ID T4 models like Space Marine Characters, Wulfen, Eldar Jetbike HQs, Ork Nobz, Tyranid Warriors, GK Paladins, etc. when they have been reduced to T3 by Enfeeble.
4 – T6 units like most Tyranid Monstrous Creatures, Riptides, Stormsurges, Nurgle Biker Lords, Nemesis Dreadknights, Ork Biker Warbosses, etc. become T5 when “enfeebled” and thus can be IDed with a single hit from a S10 DW Heavy Thunder Hammer in close combat.
Outside of reducing the ID threshold, Enfeeble also helps DW weapons wound more efficiently (i.e. Frag Cannons shooting solid shot at 12″ or less wound a Wraithknight on a 3+ normally, but with Enfeeble on the Wraithknight, they wound it on a 2+ which, combined with re-rolls of 1s to Wound if they are part of an Aquila Kill Team, basically guarantees an AP2 wound).
Of course, Prescience is, as always, one of the top powers (despite costing 2WCs), since it is a guaranteed Primaris and significantly increases Deathwatch unit accuracy in both close combat and shooting. Foreboding is also great for the firepower heavy DW and can make assaulting them almost suicidal with BS4 Overwatch and Counterattack, as is Forewarning to give a 4++ save to units that generally lack any defense against AP3/2/1 attacks (unless they take Storm Shields). Perfect Timing is tremendous with Deathwatch units, as their great firepower gets even better when having Ignore Cover applied to them, as is Misfortune, which can turn all those Infernus Heavy Bolter, Special Issue Ammo Bolter, and Hand Flamer hits into Rending hits against a selected target. Finally, Precognition can allow a TDA Librarian to tank attacks for his squad quite effectively and Scrier’s Gaze gives deathwatch armies critical Reserve Manipulation abilities, which is especially important for them, given their low model counts and need to have everything come in exactly at the right time. Overall, you really can’t go wrong with Divination in a Deathwatch force.
SANCTIC DAEMONLOGY –
Banishment doesn’t do much for DW armies (unless they are fighting Daemons, of course), but Gates of Infinity gives the often foot-slogging Veteran squads and Kill-Teams tremendous mobility to maximize their firepower and reduce their vulnerability to enemy attacks while Sanctuary can combine with Storm Shields on Terminators, Vanguard, and/or Veterans to give them unit 2++ saves up front, measurably boosting their survivability. Hammerhand is also exceptionally useful for DW armies, since basically every model has 2A base (due to their veteran stat-line)… with even a basic squad able to put out lots of S6 attacks (and units that have PFs/CFs/THs being pumped up to S10), this power makes DW squad downright devastating in combat, especially if they have some special close combat weapons in the unit (imagine a Black Shield with LC/PF and Hammerhand cast on the squad; normally, that is 4 x S4 AP3 Shred or S8 AP2 Unwieldy attacks on the charge, but with Hammerhand those become S6 AP3 Shred attacks and S10 AP2 Unwieldy attacks, respectively, with the chance to actually have 8 attacks if the Black Shield is fighting an enemy IC, MC, vehicle, or unit that outnumbers him and his squad). Finally, while Witchfire power are generally not the best options, Cleansing Flame gives DW Librarians the ability to deal with multiple enemy units at once, thus freeing the limited number of DW combatants to focus their “normal” shooting on other units, and Vortex of Doom gives the army access to Strength D shooting that it otherwise does have.
While other Disciplines can be quite effective in a Deathwatch army (I can think of several uses for Librarius, Technomancy, Geokinesis, and Telepathy powers right off the bat), I think that Biomancy, Divination, and Sanctic Daemonology are going to be the “go to” discipline for most players running the Deathwatch faction on the tabletop.