Operation Flashpoint: Red River
I've seen an enemy HMMWV get stuck on some debris only to pop-up across a river and waste my whole squad.
I've also see enemy just pop-up because I hit a marker, and again, waste my whole squad.
Some how the enemy AI is getting head shots on me at a consistent rate while also being able to locate me through terrain (i.e. mountains)
I like the challenge, but they need a patch fast.