The key will help to open the door to the next level. Don't think it won't be hard. You have a perfect gun helping to kill the enemies. INVASION - is the simplest 3D shooter with surviving elements in which you must survive on an unknown planet. The main idea is simple. Every location is full of various aliens who want to destroy you. You explore different locations where a key is hidden. Collect ammos, medical kits, door keys, kill opponents. The game will be thrilling for you. Good luck. FE.
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