Command your Mobile Outpost and take your Protoslag Gun to venture deep into the Signet surveillance off-limit area where dangers lurk in the dark. Collect incredible Weapon Units and amp up the firepower of the Outpost that fights with you. This game is about tower defense, first-person shooting, and real-time strategy all at the same time. Make the right play to eliminate powerful enemies coming from all directions. In Co-op Play, tally your companions to fight off enemies. Together, you will conquer many threats and challenges to reclaim the lands from Signet!