Awaken Undead

After spending the casting time tracing magical pathways within a precious gemstone, you touch a Huge or smaller undead creature. The target must have an Intelligence of 3 or less, and a CR no higher than 2. The target gains an Intelligence of 10. The target also gains the ability to speak one language you know. Your DM chooses statistics appropriate for the awakened creature, if one does not already exist.

The awakened undead is charmed by you for 30 days or until you or your companions do anything harmful to it. When the charmed condition ends, the awakened creature chooses whether to remain friendly to you, based on how you treated it while it was charmed.