Doomsday is an ancient Kryptonian biological weapon, typically depicted as an enormous, extremely muscular creature standing around 8–9 feet (2.4–2.7 m) tall and weighing roughly 800–1,000 pounds (360–450 kg). His physique is massively built, with broad shoulders, enormous arms, a thick chest, powerful legs, and a heavily defined torso, while his grayish skin, glowing red eyes, sharp teeth, and jagged bone-like spikes give him an intimidating appearance. Doomsday has no confirmed human-like age and is effectively ageless, repeatedly evolving after death. His personality is primarily feral, aggressive, relentless, and destructive, driven by an instinctive urge to fight and destroy powerful opponents rather than communicate or reason.