Create Greater Undead (5e Spell)
From D&D Wiki
|9th-level Necromancy (ritual)|
|Casting time:||1 minute|
|Components:||a humanoid sacrifice|
You must sacrifice one humanoid during the ritual, if the humanoid is revived afterwards the spell ends this does not include turning the humanoid into an Undead with the spell animate dead or create Undead. After sacrificing one humanoid you must then choose a corpse within range that corpse becomes a undead with the challenge rating of 20 or lower under your control. The corpse cannot be the humanoid sacrifice. The undead is under your control for 24 hours, before the 24 hours up you must cast the spell again without the humanoid sacrifice to keep them under your control. If you fail to do so you lose control of the undead and it gains it's own consciousness.