The Infernal Engine is a large, box-shaped, apparently mechanical Heartless with four large black wheels, two on either side of its body. It appears to be predominantly made of wood. Its face takes up its entire front side, with a large, red, jagged mouth with yellow "lips" on its lower half, and a black "forehead" with silver, metal additives on it. Its eyes are a glowing yellow color and its Heartless emblem is in the middle of its face. There is a wooden guardrail on its top decorated by yellow and red patterns as well as four white spikes. The Infernal Engine is able to release a battering ram, hammer, and boxes from its mouth.