Once reunited with Keller, Cross and Green work to seal the dimensional tear to stop the invasion. The military arrive and try to remove all personnel as well as the alien force. After resetting key equipment to prevent a second dimensional rift, the two are tasked with preparing a satellite for launch. The satellite, which is launched by Freeman in Half-Life, is used in tandem with ground-based equipment to significantly weaken the effects of the resonance cascade.[9] Keller tasks Cross and Green with activating this set of prototype equipment, a displacement beacon, which through the satellite may be able to seal the dimensional rift. However, after activating the beacon, both characters are caught up in a "harmonic reflux", a distortion caused by the rift. Despite this, Cross and Green are able to return safely and Keller congratulates them on their success.[10]