Death beam

A black beam emits from your palm and a creature you can see must succeed on a Constitution saving throw (DC 20) or take 3d10+10 necrotic damage. if the creatures (con) saving throw is below 15 the creature begins turning into an undead servant. they take the stats of a zombie but they keep there normal ability scores and HP. You can mentally command the zombie and it will follow you until it dies or you dies. this transformation can only be reversed using a wish spell.