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The game takes place on Vega 4 in the city of New Shanghai. During some underground construction, a work crew came upon a species of aliens, who attacked the workers and then quickly moved to the surface. The people of New Shanghai, unfamiliar with the xenomorphs, were quickly overcome, but not before broadcasting a distress signal to Earth which was also received by a passing ship of Predators. The Predators went to Vega 4 to hunt this species of aliens rather than hunting down humans as prey because it was decided that these aliens were more of a challenge than humans. After completing the stages of Vega 4 the player travels to the Orion Nebula, the region of space where this species of Aliens came from. The final boss, the queen alien, can be found there.

[edit] Stages

There are 6 stages which each either 1 or more parts in the stage. 5 of the stages have alien bosses who each possess different powers from the animals they gestated in during their life cycle.

1. Stage 1 boss: Aquatic Alien, having emerged from a dolphin.
   1. City
   2. City Sewers.
2. Stage 2 boss: Gorilla Alien, a beast that came from an ape.
   1. The Woods.
3. Stage 3 boss: A phalanx of Chestburster alien young.
   1. Vega 4 Alien Hive.
4. Stage 4 boss: Bat Alien, a winged alien that emerged from a giant bat.
   1. Space Port.
5. Stage 5 boss: Snake Alien.
   1. Spaceship 1, corridors
   2. Spaceship 2, engine room
   3. Spaceship 3, bridge.
6. Stage 6 boss: The Queen Alien.
   1. Orion Nebula.
   2. Alien Hive (looks similar to stage #3).