What does toads beetle bats light on you from the tempest mean?

"Toads, beetles, bats light on you" is a line from the play The Tempest by William Shakespeare. It is spoken by the character Caliban, a deformed slave on the island of Prospero. Caliban is cursing his master, Prospero, and wishes that all manner of creatures would attack him. The phrase "toads, beetles, bats" is meant to evoke a sense of disgust and revulsion, and suggests that Caliban wishes Prospero would be covered in these creatures. The word "light" is used in the sense of "land" or "settle", so the line means that Caliban hopes that toads, beetles, and bats will land on Prospero and plague him.