- Estimated achievement difficulty: 8/10
- Offline: 23 [615

- Online: 24 [385

- Estimated time for 1000

- Minimum playthroughs: 4 recommended
- Missable achievements: None!
- Glitched achievements: Most campaign achievements tend to be a little bit glitchy but none are entirely broken.
- Cheats disable achievements: No Cheats available
Step 1: The campaign playthroughs
Note: Most campaign achievements behave glitchy - this guide will try to to give you hints and pointers to have as few problems as possible... unfortunately this is still not a 100% guarantee.
Note 2: Play on the lowest difficulty except for your third playthrough. Do not skip the credits at the end of the game or some achievements might not unlock.
Step 1.1: First playthrough
Achievements: "Survivalist", "Real Time", "Interval-Achievements", "Medic!", "Bullet Sponge", "Environmentalist"
Your first playthrough should have the goal to memorize most of the campaign and get familiar with the game mechanics. While it may sound harsh to go for Survivalist and Realtime on your first run, this really helps to build up your abilities crucial for beating the game on extreme (see Note below). The only achievement you have to keep an eye on is "Environmentalist" as all the others will unlock automatically or over time.
Note: If you accidentally activate SloMo or die quickly hit the guide button and go to the dashboard as this will (in most cases) still enable you to get the achievements - simply reloading a previous save or quitting to the main menu will not work though.
Step 1.2: Second playthrough
Achievements: "Ammo Hog"
Your second playthrough should focus solely on "Ammo Hog". If you feel amitious enough you can try to go for "No Juice" as well but keep in mind that less SloMo means a harder time rushing your enemies and you need to get in close for the melee kills - less health means possibly having to waste ammo on the ghosts in the last intervals. Use this playthrough to familiarize yourself with the SloMo function.
Note: There are a few places where it is inevitable to shoot - in those cases use your Pistols or the Type-7 if you have it. Go for headshots.
Note2: Dying or reloading seems to count as double ammo. Employ the guide-button trick again. Moreover shotgun shells count as multiple rounds while the MOD-3 seems to glitch the achievement completely - Grenades on the other hand do not seem to have an impact.
Step 1.3: Third playthrough
Achievements: "Fearsome", "Fearless", "Explorer", "Exterminator", "Intel", "Explosives Expert", "Slow Jo", "Vermin Badge", "Suicide King"
By now you should be familiar with the campaign and the controls, so now is the time to switch the difficulty to extreme. Since you have to be careful about every enemy it's only reasonable go for the collectible-achievements as well as "Exterminator" on this run. The other achievements can be done along the way without much effort.
Note: Tips for beating extreme are (i) use cover! a lot! (ii) use SloMo! never pick a fight with a drained SloMo-bar! (iii) employ the right weapons for the right situations
Note2: Exterminator can be quite a hassle. Look here for some tips.
Step 1.4: Fourth playthrough
Achievements: "No Juice", anything that did not unlock the first time
The last playthrough is basically for the remaining "No Juice" achievement since that somehow does not mix well with the other achievements. Furthermore it is intended to get any achievements that did not unlock on a previous attempt (and believe me the chances for that are high).
Note: The guide-button trick still works if you accidentally picked up a booster.
Step 2: The Instant action maps
Since you are now almost a F.E.A.R-veteran these 2 achievements should not pose much of a problem. Employ the same tactics as you did for beating the campaign on extreme and don't be afraid to spend first aid kits or ammo. If you still have problems, a video-walkthrough can be found here.
Note: Unfortunately these achievements are glitchy too. To be on the safe side, play through the instant action maps in order and offline.
Step 3: Multiplayer achievements
The only thing that is left now are the multiplayer achievements which must all be done in ranked multiplayer games. All achievements are obtainable with only one other person, use the forums to find a partner.
As far as the achievements themselves are concerned focus on the weapon achievements first. Regarding the weapons that you already come equipped with it is fastest to start a CTF-match on rubble and keep spawn killing your partner (the ideal spot for this is to wait in front of the door leading to the flag-room and your partner will spawn in the courtyard next to you - just keep your distance to the spawn point). You can also get Belly Gunner and Sapper on that map.
For the "special" weapons play Death match games on Campus as this map holds all the missing weapons and is easy to navigate. In addition, remember to go for the 150 headshots over the course of boosting the weapon achievements.
Once you are done with these finish up the rest of the multiplayer achievements ("Demolitions Expert", "Team Victory", "Fearless Flagman", "Noob" and "MP100/1000"). For a quick way to gain games played start up Elimination matches on High Tech and have one player blow himself up with the nearby fuse box.