Tome of Convenient Rats

Special Rules
-You may use a bonus action, roll a D100, then
summon a Swarm of Rats in an unoccupied
space adjacent to you.
The Swarm shares your initiative count and
takes its turn directly after yours. on subsequent
turns, you may use your bonus action to give
the Swarm a command, if not given a command,
the Swarm will defend itself. after ten minutes,
the Swarm gets eepy, and returns to the tome.