Undead Thralls + Summon Undead

[Ir0ns0ul]

Hey folks,

TLDR: Assuming Undead Thralls applies to Summon Undead and considering HP, DPR, damage type and special ability effectiveness, it seems this ability makes the undead creatures superior to all other options up to spell level 4 (I'm excluding Summon Greater Demon). Am I perhaps missing something about the other Summon spell?

My Necromancer just reached level 7 and I decided to give a chance to the new Tasha's Summon spells after my group suffered big time to defeat some nasty creatures with spell resistance -- my Wizard was not able to deploy a single debuff/control spell and did not contribute so much to the combat (my skellies from Animate Dead were gone after previous encounters). What I realized was that Undead Thralls could improve Summon Undead a lot, and perhaps give me another good Concentration spell option whenever facing enemies with spell resistance, legendary resistance and alike.

The stat block for an upcasted Ghostly Thrall would be

AC 15
HP 47 (30 + 10 upcast + 7 Undead Thralls)
Fly speed of 40 ft
Minor resistances and immunities
Some flexibility with movement thanks to Incorporeal Passage
And more importantly an amazing Deathly Touch attack causing 1d8 + 3 + 4 (spell level) + 3 (Undead Thrall prof) necrotic damage with the rider effect of causing frighten (WIS save) until target's next turn. This is 14.5 average dmg of a very good damage type.


In terms of comparison for each item:

Best AC is 17 from Summon Construct, but they only cause bludgeoning damage and have inferior HP (40).
Best HP is 50 from Summon Elemental & Summon Shadowspawn, Elemental just suck hard, but Shadownspawn is a viable option with comparable DPR (13.5), good damage type (cold) and nice special abilities (Dreadful Scream) that actually causes similar frightened condition.
Fly speed of 40 ft is the best possible, but important to notice that Ghostly attacks at melee distance, so Fly speed doesn't matter so much.
Immunity to Poison and Necrotic is the best across all other. Shadownspawn only has Necrotic resistance, Elemental grants Resistance against some random energy types. Condition immunities are good as well.
Best DPR is Shadowspawn once again (13.5). Summon Fey has a better DPR number (14.5), but the damage type quite inferior (nonmagical piercing). It's important to reinforce that Ghostly form offers a free frighten attempt for each attack, which is great and doesn't bring any friendly-fire concern like Shadowspawn or Aberration (Star Spawn) special abilities.


Does my comparison make sense? Am I missing or overlooking something?

(PS: I know ranged attack is far superior, especially if we consider Fly speed, which makes Beholderkin from Aberration quite good, but I have my basis covered for ranged with my Skeleton army from Animate Dead, so I don't bother to actually keep my summon engaged in melee all the time)

[ATHATH]

Summon Fey has a better DPR number (14.5), but the damage type quite inferior (nonmagical piercing).
Correct me if I'm wrong, but can't summoned fey spirits wield (and use in their Multiattack) magical shortswords that you give them?

[Valmark]

Keep in mind that Undead Thralls works on undeads you 'create'- you aren't creating an undead with Summon Undead, so you should probably ask your DM wether it applies or not.

That said, your comparison is mostly fine. It should be noted that the hp will keep raising with levels (so SU would become better then others that scale with +10 hp each spell level) and that the Fey spirit's damage is half Force and can use magical weapons if you got them.

EDIT: ninja'd on the magical weapons.

[Ir0ns0ul]

My DM already approved Undead Thralls to work with Summon Undead without any issues. He even made the argument that this is the only spell with a different school among all others (Necromancy > Conjuration) and probably this was the design intent since always.

About the Summon Fey, well, I actually never thought about giving them magical short swords. This would mitigate their terrible damage type. Good insight, thanks! However I believe Ghostly Thrall would still be superior in terms of HP, immunities and at-will frighten attempt on each attack. But if looking for DPR only, a Summon Fey with a Flame-Tongue Short sword would be nasty!

[MaxWilson]

Hey folks,

TLDR: Assuming Undead Thralls applies to Summon Undead and considering HP, DPR, damage type and special ability effectiveness, it seems this ability makes the undead creatures superior to all other options up to spell level 4 (I'm excluding Summon Greater Demon). Am I perhaps missing something about the other Summon spell?


For a Necromancer yes, it's the best of the Tasha's spells, but Danse Macabre, Animate Dead, Conjure Elemental, Conjure Minor Elementals, and sometimes Summon Greater Demon and Polymorph are still better.

[ATHATH]

Also, if you have a reliable way to poison enemies, such as a Way of Mercy Monk, the putrid summon becomes very, very good. Paralysis is no joke.

[ATHATH]

Best AC is 17 from Summon Construct, but they only cause bludgeoning damage and have inferior HP (40).
Note that, due to a possible typo, a construct spirit from a level 4 Summon Construct spell will actually have 55 HP, not 40 HP.

[Ir0ns0ul]

Note that, due to a possible typo, a construct spirit from a level 4 Summon Construct spell will actually have 55 HP, not 40 HP.

Oh shoosh, you are correct! Thanks for the advice.