Bowser (voiced by Kenny James) is known as the Koopa King, and is the chief rival of Mario and Luigi. He is also an enemy to Pooh and Ash in Pooh's Adventures. His wife is Mistress 9, and his son is Bowser Jr.
- Bowser will become Jeffrey's enemy in Jeffrey, Pooh & Friends' Storm Adventures of Wild Wild West.
- Bowser will appear in Jesse, Xion, and Luigi's Mansion.
- Jaden and Jeffrey will face Bowser again in Jeffrey, Jaden & Friends' Storm Adventures of Super Mario Sunshine.
- Jaden and Jeffrey will face Bowser again in Jeffrey, Jaden & Friends' Storm Adventures of Super Mario Galaxy.
- Bowser becomes Juniper Lee's enemy in the eighth episode of the Juniper Lee's Adventures Series titled Super Smash Sister. He is one of the many video game villains who help rebuild Metal Sonic
- Bowser may face Aaron and Arik in the future.
- Bowser will appear again in Jeffrey, Jaden, Hiccup & Friends' Storm Adventures of Super Mario Odyssey.
- The Rogues attack an airship transport convoy to steal supplies, which angers Bowser and causes him to align with Director Krennic and Don Greyhound.
- Bowser has a good rapport with Lucifer and even teams up with him on occasion.