In EARTH X, Captain America, the Fantastic Four, Thor, the Hulk and the X-Men discovered that their purpose - and the meaning of all super heroes and mutated people in the universe - was nothing more than to protect their host planet, in this case Earth, from outside invasion. They learned super heroes are merely biological antibodies to protect a growing embryo within the Earth. An embryo for the Celestial race: This is the way these Gods fought back - only to cause a terrible ecological imbalance, a rift at its core that in time would wipe out all life on the planet. In UNIVERSE X, Captain Marvel was reborn on Earth years after his death. But he also still claimed to walk in the realm of the unliving, where Earth's fallen champions still exist. Mar-Vell led a team of heroes in a quest for the greatest weapons of mass destruction on Earth, suggesting this would limit the destruction caused by the growing power struggle on the planet. But this was not the only reason.
