what i believe that is happening with the realiistic achievement, is that some of you play solo for a little bit, then hop onto live, to play co-op, and you join with someone who is already in progress (that means you didnt get into the lobby, you went straight into the mission.).
and while doing that the game recongnizes that you beat the level on the realistic difficulty, but the portion for achievements dosent recongnize you having completed the level.
Example: you join a co-op game on realistic difficulty on the level NEGOTIATIONS (the 1st level) and you connect after your partner killed the very first guy. you will get credit for completing the level on realistic difficulty (check mark) but, you will not get credit for completing the game on realistic, so then you will have to replay the first level again, and it should unlock when you complete that level.
The only problem that i had was completing SHOWDOWN on Estate, and the PFC achievement. i joined a co-op game, and we beat it, but i didnt get the completed Estate achievement. then i hosted a game, and then i beat it, the 2 achievements poped up; completed Estate, and copleted the game on Realistic.
And also, when they fix the PFC achievement, what will we have to do to activate it. Thanks.
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