Clone Force 99, known as the Bad Batch, was a squad of 5 genetically enhanced clones. Each of these special force commandos had a specific mutation designed to make them exceptional warriors. An unexpected side effect of these mutations enabled them to resist the programming chip embedded in their heads. Instead of blindly following Order 66, they defected and became mercenaries.

Hunter, their leader, had exceptional senses and hand to hand skills. Wrecker was extremely strong, Crosshair had outstanding sight and marksmanship, Tech had superior intelligence, and Echo had cybernetic implants which allowed him to interface with computers and droids.