Pet Slime

The Pet Slime buff is caused when the player uses the Petri Dish item. This item can be used indefinitely. The buff gives the player a slime pet follower, and lasts until the player cancels the buff or dies. Like other pets the slime does not take damage, nor deals any. It can however block arrows from hitting the player, given it's situated in the arrow's path. Other than that it will simply follow the player around as a vanity companion.