Ok, this is only for Splitscreen.
On the level where there are to bases, a blue and a red, and it is snowy, with a cliff in between the bases, I forget the name of the level but anyway, Go to near the blue base and there should be a ramp heading up to the portal that takes you to the blue base, drive a tank up there and point the front toward the portal and park it and get out. Next, go get a ghost and ride it up the tank, the game should glitch and you should be basically standing on nothing. This is a great sniping spot and very hard for the other players to find you. This hint should take a few tries as it is kind of difficult.
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