Chapter 1 Episode 20 Back to Mario and Luigi This episode was made by Nuke
I like to think that 1-up mushrooms are powerful enough to the point of where they just work on anything that's "dead". Apparently, the people behind "Mario's Castle Calamity" had the same idea on that front. No wonder 1-up mushrooms are so valued eh? No, I don't have an explanation as to how 1-up mushrooms work the way they do. Heck, it's never even explained in the Mario Bros series, to my knowledge.