Roger the Potted Ghost is a character in the Yoshi series who appears in Super Mario World 2: Yoshi's Island. He is located in the final castle of World 2. Roger started off as a lifeless flower pot, but then transformed by Kamek's magic into a large ghost named Roger. He's amorphous, but his face resembles Dangling Ghosts and Caged Ghosts.
To defeat him, Blue Yoshi had to push Roger and his pot over the edge of the platform that they were on. This process was a very hard one indeed because two green Shy Guys were pushing him in the opposite direction to prevent you from destroying him. Throughout the battle Roger will lunge at Blue Yoshi knocking him/her away. He also shot blue flames which home in, forcing the blue dinosaur to stop pushing and get out of the way. If the Shy Guys are pushed off before Roger is he will not be able to move and he is poorly helpless.
In Yoshi's Island DS, there are enemies called Potted Ghosts which are smaller less powerful bosses unlike him.