also some people may ask what glitch am I talking about. I will explain it to you. Say for example you have 4 people in an Extinction game. When you get to the part where you arm the nuke and the meteors fall and block your path, you can make both of the meteors not fall. All you do is arm the nuke and have one player walk off the edge at the nuke and die. then about 50 feet to the right(up on the hill next to the really high porch) his dog tag will appear and you go revive him(i suggest have the medic revive him). Then I swear to you it is a straight shot to the helicopter with no stops along the way. Makes the ending very easy.