Although it's missing some lava at the "end" of the rat-run (Is it possible to put in calls for lava/acid water pools for the map editor in the future?), this is my multi-story homage to the classic Bowser boss battle from Super Mario Bros.
Amoebas and Dragons work very well - haven't managed to spawn a giant Skelebot to test it on yet mind you, but should work a treat I think! Constructive crits more than welcome.
EDIT: Updated using new lava/water feature