They are an obvious parody of the MarioBrothers. However, they use a range of contruction tools as weapons, like jackhammers, explosives and, of course, hammers, hence their title. Neither of them is named individually and are only referred to as the "Mad Hammer Bros."
The Red Hammer Brother is the larger one of the two and is a parody of Mario. He has a small red cap, a thick unibrow (which obscures his eyes), a large red nose, a jagged mustache, dark tan stubble, rather hairy arms, and red overalls.
The Green Hammer Brother is the lankier of the two and is a parody of Luigi. He has a large green cap (which obscures his eyes), a pointy nose, a straight and well kept mustache, grey stubble and green overalls. He is also seen with a tooth sticking out of his mouth when he isn't talking.
They both also have a stereotypical Italian accent.
- Ironically, out of all their weapons, their hammers are used least.
- They use contruction tools as weapons, but mostly demolish with these tools rather than construct or create.
- They are references to the MarioBrothers. Their name could be a reference to the enemies from the same franchise. They also use the same jump sound effect from Super Mario World whenever they jump. In The Legion of Evil, they exclaim "MAMA-MIA" when being spray-painted by one of Jenny's project partners.
- They are also very similar to Wario and Waluigi of the same franchise, in their villainous, mean, destructive ways, and grotesque and gruff appearances.
- They don't exactly see eye to eye, as they are heard arguing in Sibling Tsunami, saying how the other smells.
- They are often heard calling others spazzes.