Swarm of Rats

Speak a word of power and summon an horde of fiendish spirits that take the shapes of a Swarm of Rats in a point you can see.

On each of your turns, you can use a bonus action to mentally command the Swarm if it is within 60 feet of you. You decide what action the Swarm will take and where it will move during its next turn, or you can issue a general command, such as to guard a particular chamber or corridor. If you issue no commands, the Swarm only defends itself against hostile creatures. Once given an order, the Swarm continues to follow it until its task is complete.