Shadow Serpent (voiced by Adam Gardiner) is a snail-like Toxic Mutant who could steal shadows from other living beings with his tongue rendering them motionless. He was summoned by Bigs in order to do battle with the Mega Rangers and their new ally Robo Knight. A formidable warrior who is cunning in battle and a glutton for shadows. However, his overconfidence proves to be his undoing as the teamwork between his enemies allows them to overcome him. He is compared by his comrades to Creepox because of his strength and arrogance. He wields spikes in battle, can shoot lasers and breathe fire.