Mikey is a teen mutant ornate box turtle with blue-green skin, a bright yellow plastron, and a blue-grey carapace with a yellow pattern. He has geometric yellow markings on his shoulders and thighs, black eyes, a tooth gap in the left side of his upper jaw, three fingers on each hand, and two toes on each foot. He wears an orange bandana with short bandana tails, matching wristbands and socks, and matching knee pads with red faces on them (a dead face on the right and a smiley face on the left).