On New Kroy, Mission 1, go to coordinates 150, 180 while you are above the clouds. Dive straight down slowly, and you will enter a half-room with two bunkers. Destroy the bunkers. The floor will have a picture of "TRI: Terminal Reality Incorporated." Make sure there are enemies underneath the clouds and in the half-room with you at this point. Find the tunnel, go in, and when you come out the other side, turn around and blow up the four small gray buildings that were directly behind you. Underneath one is a tunnel exit, where you came out; underneath another is a tunnel entrance. Go into it. When you emerge from the other side, the enemies that were in the half-room are now in the underground room.