I am wondering if swarms damage other swarms of the same kind if they occupy the same square, or other animals of the same species/kind that move through, or even join them.
An extended example shows the problem:
A 6th level druid uses his Wild Shape spell and turns into a tiny bat (animal). Then he casts one Summon Swarm of Bats inside a globin's square, 30 feet from him. Then he casts another on his next turn, in the same square.
Does one Bats Swarm damage the other? Why or why not?
After the goblin is killed by the swarms, the druid stops his concentration and moves into the square of the swarms as a bat.
Is the druid in Bat Form damaged by the Bat Swarm? Why or why not?