I found this during a Weapons Only run. Orange seems to be completely invincible during this course. He grabs two stars in quick succession right at the start. The second one seems to turn him back to normal for some reason. Then he gets run over by the cart several times, steps on mines, gets hit by hammers, shot with lasers and burned by flamethrowers, all to no avail. It's like the star invincibility stayed on, but not the rainbow colours or the insta-kill ability.

While playing (Bomb it, 1 player, easy), I (Green, bottom right) activated the ice powerup, it intersected with a bomb explosion and somehow turned into a new powerup. The original game doesn't usually generate new powerups, so I don't know what happened. I haven't seen anything like that before.