Hivemind Soul, Variant (5e Class Feature)
From D&D Wiki
Prerequisite: 5th-level warlock
With this invocation when you attack creatures that have lower intelligence and hit points score then you can possess his body as an optional reaction when your hit points go to 0, when you are in this new body the shape of the creature that you possessed assimilate every attribute of your old body, the hit points of the creature are now your hitpoints and you just can use cantrips for one hour.
At Higher Levels. When you use this Eldritch Invocation at 11th-Level Warlock you can divide your mind into more bodies that are equal to your proficiency bonus for one hour after that you become the creature with more hitpoints.