Shadow Mario was originally thought to be a clone, but Shadow Mario is his own unique character in Super Smash Bros.: Going for Gold.
B: Paintbrush (Shadow Mario uses his paintbrush like a sword to hit opponents.)
B-Up: Paint Teleport (Shadow Mario teleports through a paint teleport. If others touch it mid-air, they will go into a helpless state.)
B-Side: Paint Mop (Shadow Mario "mops" the floor with his paintbrush, creating a slippery goop. If an opponent touches it, they will be damaged, and if they run in it, they will trip.)
B-Down: Polluted Piranha Plant (Shadow Mario summons a Polluted Piranha Plant. It will stay for 10 seconds and will attack any opponnents near. Takes 20 seconds to recharge (10 seconds while the PPP is these, 10 seconds after.))
Final Smash: Giant Paintbrush (Shadow Mario swings his now giant paintbrush around, damaging foes.)