Note: This requires that the free FanPack maps map be downloaded. There is a way to earn some fast A.C.E.S. points on the CQB Dark map. It is best to do this on solo so that no enemies are triggered before you are ready for them. Start a Terrorist Hunt offline and make sure Lone Wolf is on. By doing this, your AI partners will not spoil anything for you. When the game loads, immediately change over to your pistol. The Desert Eagle is recommended because it is a one shot killer at close range. Start walking to the corner of the wall on your left. As you near it, sprint around the corner and go up the ladder. The man at the end of the other room may shoot at you or call for back up, which is perfect. Do not stop to engage him or his friends. Climb the ladder quickly and take cover beside the concrete wall crouched down so that no one below can shoot you. Aim at the ladder and wait. They will come up one by one. When the count reaches 37 terrorists to go it is time to trigger more. Go down the ladder and go to the room where you started. Go out into the courtyard ahead. Move behind the pallets of sandbags. Move just so you can get a shot on the person in the building across from you on the right side of the doorway. Shoot him and run back for the ladder. Go back up and repeat the process. The count should now be 29 terrorists. Run across the map to the other ladder, entering at the closest door to you (behind the broken down van). Shoot at either of the men you encounter (in the window of the middle building or the corner of the far right building) then run for the ladder and go up. Repeat the process. Allow one minute to pass without terrorists to make sure it is safe to continue. Move to the wall behind you and do not leave the top of the ladder. Fire a few rounds then go back to the ladder. Repeat the killing. Keep moving out into the outer perimeter of the building with the ladder and you should narrow it down to about three to five terrorists that will not fall for your trap. Hunt them down and kill them. You can clear the map on your own. You can do this under the Realistic setting at high enemy density. Every kill you make should be while they are on the ladder and you are behind them. You will get Kill At Close Range or more often than not, Kill Opponent From Behind A.C.E.S. points. Kill 40 terrorists like this and for 120 A.C.E.S. points per round.
To earn a great amount of A.C.E.S. for Marksman and CQB and a little bit of Assault, equip a sniper rifle with 6X12 scope Note: Any of them except for the first sniper rifle will work, preferably the automatic one. Go to Story mode and to the chapter "Monorail". You should begin with two doors in front of you. Do not open them yet. There are two supply boxes. Open one, and it will give you more ammunition for your sniper rifle. After that, open the doors and order your companions to guard the left entrance of the monorail. Note: If this is not done, you will be killed from behind. Take cover, but not behind the plants. Also, do not cross the monorail hall or you will either be killed or will not get what you are looking for. The methods to getting A.C.E.S. after that are as follows.
CQB: Once behind cover, pull out your sniper rifle. Do not get out of cover. You need to scope twice with your sniper. You will see the screen go into focus. Then, blind fire at the turrets and men, but beware, some rush. Your companions should take good care of them, though if you placed them at the correct location.
Marksman: This is a little harder as it involves you not blind firing, but coming out of cover to shoot. Scope into any of the men you see and always do a head shot. Some may be too close for the "Long Range" A.C.E.S., and if you simply shoot them on the chest it will not get you the points. Some may rush, but once again those two soldiers will help you.
Assault: Advance through the monorail to your right. Take cover behind a blue box. A shielded opponent will emerge. Snipe him on his leg or arm and he should fall. Advance forward. Once you have reached the area where enemies charged down the stairs, there should be another shielded opponent on the opposite side. You can either let your companions take care of him, or you deal with him personally. Doing this tactic should get you a massive amount of A.C.E.S. After every time you finally kill the shielded opponent on the opposite side of the bridge, just reload checkpoint and do it all over again.