Ok, this one probibly is only useful in 1-1000 times you play, but it's still fun to use.
(Step#1) Get an ATV and find a large rock, perferably somewhere around a large fight.
(Step#2) Get out of the ATV and get back in [remeber the side you got in on], drive up next to the rock so the side you got in on is touching the rock.
(Step#3) Exit the ATV, bam! you're inside of the rock. It may not seem like it, but you are. Getting out of the rock my be difficult, try jumping or pack some grenades to off yourself.
The rock provides invincibility, so dont worry about anyone seeing you or damaging you, the drawback is you CAN see them but you cant shoot them, BUT you can pop out and blow there brains out or set a router, motionsensor, or even an Agis shield generator if the rock is large enough to fit it.
Well have fun with exploit, hope you like it.
./)/)
(0.o)
(>.<)
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