The Soulless Patron - Necromancer Warlock Subclass based on M:tG's Liliana Vess

[Man_Over_Game]

This one's really hard to balance, due to the fact that armies in 5E are....complicated to get right, but I'll do my best.

Level 1: This feature does seem a little strong. 2 undead at the cost of a repeatable cantrip with no limit or resource?
To put another way, you could attack it and deal 1/3 of it's life, and you'll kill it after 3 hits, removing one character from the enemy side.
OR
You can make it try a Wisdom saving throw, which has about a 1/2 chance of failing, to remove one character from the enemy side and gain one on your side.

Not only is it effectively removing undead in almost twice the time that a normal cantrip would, but it's also being twice as good since it then makes that undead an ally rather than just dead. And while you can only keep 2 zombies, there's nothing saying you can't do this forever.

The other issue is that it's not applicable in many situations. Only the most specific campaigns would be guaranteed to have undead at level 1, which is one of the issues with the current PHB Ranger. In this instance, it just makes you incredibly overpowered in a situation that has low level undead, or have no feature at all. If this was ever applicable, it's because the DM decided to give you a handout.

I'm not terribly sure how to make it applicable, though.

Drat, ran out of time for more review, will follow up later.