Animate Massive Undead

This spell creates a massive undead servant. Choose a pile of bones or the corpse of a huge or larger creature within range. Your spell imbues the target with a foul mimicry of life, raising it as a skeleton if you choose a pile of bones or a zombie if you choose a corpse (the DM may have the creature's game statistics, or you may need to use a conversion table).

On each of your turns, you can use a bonus action to mentally command the creature you made with this spell if the creature is with in 60 feet of you (if you control multiple creatures, you 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 turn, or you can issue a general command, such as 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 creature is under your control for 24 hours, after which it stops obeying your commands. To maintain control of the creature for another 24 hours, you must cast this spell again before the current 24 hour period ends.