Bag of Infestation

This small, soiled leather bag constantly wriggles. 

When a creature reaches in, they may pull a rat swarm out of it up to 3 times per day.

If the bag is turned inside out, a Rat King Swarm spawns and the bag has a 50% chance of being rendered powerless.

The swarms spawned by the bag view the being that drew them out as allies and will follow simple instructions.