Shroob



A Shroob is an evil mushroom creature found all over the game Mario and Luigi: Partners in Time. They conquered the Mushroom Kingdom of the past. There are many variations including Shrooblets. Their leader is the Elder Princess Shroob and the second in command is Princess Shroob. Their home planet is shaped like a mushroom. They stared into space looking for a planet to conquer while they were on their homeplanet.

All bosses (with the exception of Bowser) have something to do with or are Shroob creatures/Shroobs.

Mario & Luigi: Bowser's Inside Story
It was revealed during Mario & Luigi: Bowser's Inside Story that Bowser froze several Shroobs and preserved them. Mario and Luigi fought them and defeated them, getting the Magic Windows Attack Pieces. They were noticeably stronger than they were in Partners in Time.