- "Don't call us a gang. Don't call us criminals. We are the law. We are the future. Gotham City belongs to the Mutants. Soon the world will be ours."
- ―Mutant Leader[src]
The Mutant Leader was the boss of the vicious mutant gang in Gotham City in 1986, operating out of the Gotham City dump. He became popular amongst the impressionable male youths of Gotham who he encouraged violence in. Calling themselves the Mutant Gang, his followers brought Gotham's crime to a historic all-time high.
After Batman attacked the Mutants at their headquarters, he called Batman a coward for using rubber bullets to mow down his followers rather than killing them and hiding in the batmobile. The Mutant Leader challenged Batman to a one-on-one fight, where he nearly killed the Dark Knight. As he was about to impale Batman with a crowbar when Carrie Kelly (in her Robin costume) distracted him long enough for Batman to subdue him.
The Mutant Leader was arrested and brought to prison, but when the mayor tried to negotiate with him, the Leader murdered him without second thought. Following a plan with Batman, Commissioner James Gordon deliberately released him, and he found the entire Mutant Gang assembled near a sewer outlet. Batman then ambushed him, leading to a bloody rematch. Despite his physical superiority, the Mutant Leader was no match for Batman's strategic mind; he chose the mudhole to slow the leader's movements, and he then inflicted several major wounds. Eventually, Batman overpowered the Mutant Leader, and the Mutants disbanded into smaller gangs.
The Mutant Leader seems to be in peak physical condition, as he manhandles an older version of Batman in their first fight. He is bigger than Batman, very savage, and incredibly strong and fast. Additionally, his nails and teeth appear to be filed to points, and his skin appears a greyish hue.
It remains unclear as to whether or not he possesses any true mutations.
Appearances in Other Media
The Mutant Leader appeared in an episode of The New Batman Adventures, titled: Legends of the Dark Knight. He was voiced by Kevin Michael Richardson. Here he appears in an imaginary sequence made up by Carrie Kelley, a teen in Gotham who is picturing being Batman's Robin.
A LEGO version of The Mutant Leader appears in The Lego Batman Movie alongside other Batman villains working for the Joker.
The Mutant Leader makes his live action debut in the fifth season of Gotham where is is portrayed by Sid O'Connell. He is the leader of the Mutant Gang during No Man's Land when Gotham is hit by a cataclysmic earthquake.