I have been working out the math for maximum undead from a RAW necromancer straight out of the PHB. The spell castings of Animate Dead below are considering the undead are already animated and the necromancer is just reasserting control.
At 20th Level:
3rd x 3 animate undead (4 each) = 12 skeletons/zombies
signature spell 1x animate undead = 4 skeletons/zombies
4th x 3 animate undead (6 each) = 18 skeletons/zombies
5th x 3 animate undead (8 each) = 24 skeletons/zombies
6th x 2 (3 each) = 6 ghouls
7th x 2, 1x finger of death = 1 zombie per day, 1x create undead = 4 ghouls
8th x 1 create undead = 2 wights (can control 12 zombies each) = 24 zombies
9th x 1 create undead = 3 wights (can control 12 zombies each) = 36 zombies
Command Undead Ability, Mummy Lord (only has 11 INT) his spells:
3rd x 3 animate undead (4 each) = 12 skeletons/zombies
4th x 3 animate undead (6 each) = 18 skeletons/zombies
5th x 2 animate undead (8 each) = 16 skeletons/zombies
6th x 1 animate undead (10 each) = 10 skeletons/zombie
Arcane Recovery:
5th x 2 animate undead (8 each) = 16 skeletons/zombies
For a grand total of:
1 mummy lord
5 wights
10 ghouls
60 zombies (controlled by wights)
146 skeletons or zombies (56 of which are controlled by the mummy lord)
plus 1 zombie per day as you cast finger of death over and over and over
plus if you have a cool DM you may have a Crawling Claw as your familiar and a Flaming Skull back at the library protecting your secrets.
How is my math?
-FightKing
At 20th Level:
3rd x 3 animate undead (4 each) = 12 skeletons/zombies
signature spell 1x animate undead = 4 skeletons/zombies
4th x 3 animate undead (6 each) = 18 skeletons/zombies
5th x 3 animate undead (8 each) = 24 skeletons/zombies
6th x 2 (3 each) = 6 ghouls
7th x 2, 1x finger of death = 1 zombie per day, 1x create undead = 4 ghouls
8th x 1 create undead = 2 wights (can control 12 zombies each) = 24 zombies
9th x 1 create undead = 3 wights (can control 12 zombies each) = 36 zombies
Command Undead Ability, Mummy Lord (only has 11 INT) his spells:
3rd x 3 animate undead (4 each) = 12 skeletons/zombies
4th x 3 animate undead (6 each) = 18 skeletons/zombies
5th x 2 animate undead (8 each) = 16 skeletons/zombies
6th x 1 animate undead (10 each) = 10 skeletons/zombie
Arcane Recovery:
5th x 2 animate undead (8 each) = 16 skeletons/zombies
For a grand total of:
1 mummy lord
5 wights
10 ghouls
60 zombies (controlled by wights)
146 skeletons or zombies (56 of which are controlled by the mummy lord)
plus 1 zombie per day as you cast finger of death over and over and over
plus if you have a cool DM you may have a Crawling Claw as your familiar and a Flaming Skull back at the library protecting your secrets.
How is my math?
-FightKing