The Climax was originally a regular exploration craft operated by a crew of 50 humans. An unknown entity killed the crew, leaving the consciousness inside the ship. The entity and the consciousness merged with the ship, turning it into a life form. In order to gather energy, the ship destroyed planets, converting them into energy.
The first planet that the Climax destroyed was Heylando, the home planet of the original crew. The Climax teleported to the Uuawra system and destroyed Cubevian. The ship then used the energy to teleport nearby to Jeyron, destroying it. Due to an unknown cause, the ship was thrown out of the main universe and into an alternate universe. The boundaries of the main universe was too strong for the Climax to re-enter, but it could pass between alternate universes as their boundaries were weaker.
At some point, the Climax arrived in the Cube2 alternate universe, destroying the alternate version of Exelon. When the universe was destroyed, the Climax was thrown into yet another alternate universe, where it was trapped with no energy. It slowly found its way to an alternate version of itself (which had not been taken by the entity yet) and destroyed it for energy. However, it created a paradox which caused the Climax to overload and the life form inhabiting it died.
When the Climax destroyed the alternate version of itself, it may have caused the original Climax to be invaded by the entity. The entity may have been the Climax. If so, the Climax technically never died as it passed on to the original Climax.
The Climax unintentionally caused two species to invade other planets: The Cubians fled from Cubevian and overtook Karvor, while the destruction of Jeyron caused the species to destroy Ikhaystin and invade Exelon.
Alternate universes Edit
In the Cube2 alternate universe, the Climax did not exist. However, the Climax from the main universe was, at one point, in the Cube2 universe.
The Climax did exist in other universes, however. In one universe, a version of the Climax early in its timeline existed. It was destroyed by the real Climax.