They were summoned by the game by Walter and Danny while continuing the game. The first Zorgon spaceship first found the boys before the others and using energy cannons to attack the house while tracking them with a heat source, but the stranded astronaut, whom summoned later, removed and replaced the source and left them off course.
However, much later, Lisa turns back the water heater, returning them back to the house just a few moments before the boys and the astronaut attempted to lure the aliens with their own schemes (by burning flammable objects they can find), which also panics her in the process. As a result, instead of one ship, three Zorgon ships approach the house and invade it. The protagonists then schemed the way to deal the threat, but realizing that the game board have been thrown into the basement out of the boys' bickering, forcing Danny to sneak into that place.
As Danny retrieved the game, the Zorgons noticed him and give chase. He was saved by Walter at the last moments, only for confronting the defected robot they knocked earlier and have repaired itself. Using the reprogram card, Walter fixed the robot's programming, turned it to their side and attacked the Zorgons back to their ships, crashing them onto space in the process. They later returned to destroy the house with a large fleet, but Danny rolled onto Zathura and the fleet and the house were sucked into a black hole returning the house to earth.
Although once having a home planet of their own, they are now entirely nomadic race. Their ships are surprisingly small (about the size of a typical house). They are bent on finding materials to burn in order to fuel their ships, an action which led to the destruction of their home planet. Their names, if they have any, are never revealed.
Usually stooping over, it is very difficult to determine their true heights. They also possess very ravenous hunger and are on the constant hunt for meats.