Using this cantrip allows the caster the opportunity to possess and control one hostile until the end of the caster’s next turn. However, it is also possible that the spell backfires and the caster becomes possessed by the hostile until the end of your next turn. Both parties must roll 1D10 and whoever gets the first natural 10 or closest to a natural 10 (3 rolls each) is the party who controls the other. 

*note: If the action taken while possessed would have normally killed the character, instead of dying they remain at 1 hit point and cannot be killed until they are no longer possessed.