Leonardo is a mutant red-eared slider with lime green skin, a mustard yellow plastron, and a green-blue carapace with a teal pattern. He has two red crescent-like stripes over his eyes, yellow stripes on his upper arms and thighs, black eyes, three fingers on each hand, and two toes on each foot. He wears a blue bandana with long bandana tails, bluish grey fingerless gloves with blue trim that extend nearly to his elbows, and matching knee-high toeless footwear.