King Bowser's Castle is the final main level in Super Mario World 2: Yoshi's Island and Yoshi's Island: Super Mario Advance 3. Unlike previous castles, the player controls Green Yoshi instead of Blue Yoshi. The boss at the end of world 5-4 is Moltz the Very Goonie. In the final level, world 5-8, Baby Wario and Baby Bowser rejoin the group as they head into Bowser's Castle. However, at the end, Baby Bowser betrays Yoshi and fights the player, but is defeated. After that, Bowser, in his normal form, shows up and attacks as well. Salvo the Slime is the boss of World 1 in Super Mario World 2: Yoshi's Island and its remake.Salvo is a Slime Drop that was enlarged by Kamek.Salvo jumps at the player, trying to push them into a lava pit below his arena, though unlike most enemies, the player is not hurt by Salvo's touch.

Yoshi's Island 5-8 Boss Guide