Harry Potter - Secrets of Hogwarts

You conjure a venomous snake from thin air. A pit viper appears in an unoccupied space that you can see within range. Roll initiative for the summoned creature, which has its own turns. Although the pit viper won't willingly attack the caster, you cannot control the actions or targets of the pit viper. It is possible for the pit viper to be turned against you through magical means.