Complex sentence: Upon docking, the X-Men learn that the space station has been taken over by the alien, Erik the Red, who attempts to use the space station's weaponry to shoot down the spaceship of an alien criminal, Lilandra.
Split into simpler sentences: Upon docking, the X-Men learn that the space station has been taken over by the alien, Erik The Red. Erik The Red attempts to use the space station's weaponry to shoot down the spaceship of an alien criminal, Lilandra.