Turok

The third Co-op map is called "Breaking the Sword" and can be quite difficult without some good players. This achievement can be unlocked in a "player" match, or if you have some friends that you wish to play with then you can start a "private" match and invite them to the game. When you reach the part of the level that requires you to descend into the pit, do not climb down the ladder as this will result in you getting shot at without being able to defend yourself, instead jump down onto the set of pipes and you will be able to shoot at the enemies. It is also worth noting that in order to complete this level you do not need to reach the chopper, instead you must eliminate every enemy, there are two snipers in their towers and numerous enemies with RPGs so take it slowly and be careful.