Animate dead

The animate dead spell creates the lowest of the undead monsters -- skeletons or zombies -- usually from the bones or bodies of dead humans, demihumans, or humanoids. The spell causes these remains to become animated and obey the simple verbal commands of the caster, regardless of how they communicated in life. The skeletons or zombies can follow the caster, remain in an area and attack any creature (or just a specific type of creature) entering the place, etc. The undead remain animated until they are destroyed in combat or are turned; the magic cannot be dispelled.

Note: This version of animate dead originally appeared in the 2nd Edition Player's Handbook for Advanced Dungeons & Dragons from TSR. Its use here is for the purposes of providing context for the campaign only.