A typical swim through the small intestine

Baby Mario and Baby Luigi are trapped in the human body! Thinking that they were auditioning for Mario & Luigi: Bowser's Inside Story, they ended up in The Magic School Bus: Explores the Human Body (which is the most freaky educational game in existence). They want to find a way out without messing things up....if you know what I mean by "messing" things up.

Biological things are Donkey Kong's domain, btw.