Swamp monster II has a similar body shape to the mutant swamp beasts it spawns, though it is far larger. It has a cone-shaped body, with a massive jaw, filled with serrated teeth. It has blue skin and a stubby tail, with three thin legs on each of its sides, and a single eye stalk. It has four large tentacles, the lower two have rows of red, thorn-like growths, and the upper two each have a single massive, red, crab claw, with spikes on the inner parts. It also tries to swallow enemies.