Crystalline. As crystalline creatures, Molluks can be tough to damage. They gain natural SOAK, but are vulnerable to sonic damage and take double damage from falling, due to their more brittle nature. Molluks are immune to the Bleeding condition. Molluks can exist comfortably in a vacuum. They do not need to breathe, and their crystalline structure means that pressure differences do not cause them damage.
Bulky. Molluks cannot jump.
Natural camouflage. In rocky surroundings, a stationary Molluk can become effectively invisible.
Hurl. A melee attack sends an adjacent creature flying 3 squares plus one square per size difference and takes 4d6+5 blunt damage, inflicting the Downed condition.