Corpse Trap

You plant the seed of undeath in a corpse, which lies in wait until it can strike. Choose a pile of bones or a corpse of a Medium or Small humanoid 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 DM has the creature’s game statistics). The undead does not move or reassemble its body until a certain condition is met, which you determine when the spell is cast. You can choose for the undead to activate when a nearby object is touched, a door is closed, or some other similar condition. Once this condition is met, the undead rises and attacks any creature it can see but you.

If you choose no condition, the undead lies dormant for 1d12 days until a creature makes an Intelligence (Investigation) check to inspect the body, at which point it attacks the inspecting creature. The undead lasts until it is reduced to 0 hit points. If the undead is active but not dead after the spell’s duration ends, you lose control of it, and it becomes hostile to you. If the condition hasn’t been met within the spell’s duration, the corpse fails to reanimate. At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, you animate two additional undead for each slot level above 4th. Each of the creatures must come from a different corpse or pile of bones, and is activated by the same condition.