Cabbage

The Cabbage summons a pet Guinea Pig when used. It grants the Pet Guinea Pig buff that lasts until the player manually cancels it by right-clicking the buff's icon, or dies. The Guinea Pig will follow you everywhere you go.

It can be obtained from Golden Chests. (Underground.) Also if you have flying items (Wings,Jetboots Etc.) The Guinea Pig will fly with you. When flying it leaves white clouds behind it like most pets.