Army of the Dead

This spell can create up to 20 undead servants. Choose a pile of bones or a corpse of a Medium or Small humanoid that you can see within range. Your spell imbues the target with a foul mimicry of life, raising it as an undead creature. The target becomes a skeleton if you chose bones or a zombie if you chose a corpse (the GM has the creature's game statistics).

On each of your turns, you can use a bonus action to mentally command any creature you made with this spell if the creature is within 60 feet of you (if you control multiple creatures, you can command any or all of them at the same time, issuing the same command to each one). You decide what action the creature will take and where it will move during its next turn, or you can issue a general command, such as to guard a particular chamber or corridor. If you issue no commands, the creature only defends itself against hostile creatures. Once given an order, the creature continues to follow it until its task is complete.

The creatures are under your control for 1 hour, unless you spend another 8th or 9th level spell slot to cast this spell again.  If you cast this spell again and there are piles of bones or corpses within the range of the spell, they are animated as well.  After the time has passed the creatures collapse into dust, unable to be animated again.