the 2 brothers in charge of the island in the end have rules they have to follow, one is bad and is not allowed to do anything himself but tries to influence the others on the island. or something, maybe don't listen to him.
and mario eats mushrooms to gain powers, and some kind of magic tree to throw fire bombs things. and can jump through secret tunnels to skip levels. but once skips he can't go back i don't think.