Glitches/Mechanics

Since this expansion uses version v1.08 of F.E.A.R. (displayed as "FEAR XP v1.0 - Retail Expansion"), some glitches such as the "ladder glitch" do not work and are not present in this run. Although "object boosting" and "people climbing" may still work, they do not have any known use in the speedrun of this expansion.

Crouch glitch
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groobo's submission notes for his segmented F.E.A.R. run (no longer on the website) explained the crouch glitch as follows:

"If you want to move at running speed in areas through which you could fit only by crouching - do this: run up to eg a tunnel's entrance, MAKE SURE YOUR SPEED = 0 IN EVERY DIRECTION, crouch, now release crouch FIRST and start moving towards the tunnel. Nothing more to it."

My explanation is the following: if you have crouch bound to a scroll wheel direction, all you have to do is push yourself against the surface you want to crouch against, and flick the scroll wheel a notch to activate crouch while moving the direction you want to go (presumably forward), and when done correctly, you should maintain full movement speed while inside areas such as ventilation shafts.

Float glitch
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The float glitch, or floating, is something I was fortunate enough to have discovered (at least, I am unaware of anyone who noticed it before I did in 2013, but someone may have). By holding jump while spamming both "use" (on the ladder) and crouch, you can cause the game to place you in a floating state. You will be unable to jump while in this state, but can float around at a fixed height. You can decrease your height at will by repeatedly crouching, and can increase your height by pushing against surfaces that raise themselves, such as railings, or by utilizing the MP-50 which will push you upwards at the cost of health (direct blast = 70 damage).

Binding crouch to scroll wheel, as mentioned before for crouch glitching, can make activating floating easier, and also makes quickly lowering your height a lot easier as well, which can be useful outside of floating.

Melee canceling
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You can cancel out part of the animation performed when punching by crouching, allowing you to punch again immediately, and effectively combo enemies with punches. Since punches are similar to rockets in their damage, being able to unleash a flurry of them due to this trick makes your fists one of the most powerful weapons in the game, although obviously limited by their range.

Reload canceling
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You can have your weapon automatically reload itself if you holster the weapon after it runs out of main ammo, before it begins its reload animation. This is primarily useful for reloading the LAW in situations where more bolts are needed, such as against Nightcrawler Elites.

Door punching
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A feature not present in the original F.E.A.R. is the ability to punch open doors. Punching doors is slightly quicker than opening them normally, as when doors are opened normally, the player will usually have to wait on them to fully open to get through. Punching a door will open it as fast as possible. There are certain doors (such as those with windows inside them) that are more difficult to punch open (many requiring two punches instead of one, for whatever reason), and are safer to open manually and then 'check' them by stopping forward movement for a split second as they open, as otherwise, you would walk into them before they're fully open and lose time in comparison. It is possible to become stuck inside certain doors if you bump into them before they fully open, which is another reason to 'check' those doors.

Weapon weight
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Every weapon has its own weight to it, and as a result, it is fastest to move while unarmed, which is why you will see me have my weapon holstered at every opportunity, and holster whatever weapon I was using the moment I think I don't need it anymore. Out of the weapons that are relevant to the speedrun, the shotgun has very little weight, but the LAW, MP-50, and rocket launcher are all quite heavy.

Health
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Health regenerates when it is goes below 40. Health regenerates much more quickly when you are not moving (ladders are an exception). Body armor basically acts as a second health bar. You can carry up to 10 medkits which heal for 50 each. Abusing the regeneration mechanic can help with conserving medkits. There are times where if you go below 40 health while taking damage and are able to tell that you won't be killed if you don't use a medkit, you will be rewarded by being able to regenerate part of your health back after surviving, which can conserve a medkit.

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Run Notes

Investigation: Arrival
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I drop my pistol immediately so that I have space for another weapon later. It doesn't really save time, it merely simplifies future actions.

I perform the crouch glitch to quickly squeeze under the gates. As shown here, you can usually crouch under the first gate and stay in a slightly lowered state all the way to the next gates, so you can effectively squeeze under all of them with the same crouch input.

The stage ends by acquiring the float glitch off of the bottom of the first ladder, and then using objects around the next room to gain the height necessary enough to pass through a wall with no collision, spamming crouch inputs to reduce height, and then floating to the end. You will be seeing this same process a handful of times throughout the run.

Investigation: Underneath
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Similar to the previous stage, but with more action.

I fire the shotgun to alert the grunts above. It's possibly coincidence but ever since I started doing that, it's manipulated them into better positions. They can slow me down if they decide to do things such as blow up the barrel to my right after I climb up the ladder.

I stay a decent distance away from the Heavy Armor when he bursts through to manipulate him into moving out of the way. He can be disposed of, but doing so would be about five seconds slower than simply waiting for him to move since he takes quite some effort to kill.

The stage ends in a similar manner to the previous stage.

Investigation: Firefight
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This stage is basically all about not having a few grunts get in your way and getting the float in a reasonable amount of time.

You may notice when the stage started, I immediately jumped. This is a common occurrence that happens when the previous stage ended with floating active, and is the reason I spam crouch in the beginning. The jump happens with very little forward momentum, and I need to be on the ground to generate momentum.

Revelation: R&R
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A substantial timesaver that doesn't involve the float glitch takes place early into this stage. By lining yourself directly with the terminal near the giant logo, you can retain the ability to jump while on the terminal, so that you may jump off the terminal and onto the logo, and then jump from the top of the logo to the top floor, saving around a minute. I try to properly align myself with the terminal before jumping onto it. The top of the terminal lacks friction, and in order to be able to jump off of it, you need to jump onto it from a precise angle.

At the end, there is a turret sequence where you are expected to fend off a swarm of Replicas, but you can instead intentionally cause the turret to be destroyed, which happens faster if you take out a single grunt to cause a wave of them to spawn. The path to the next stage unlocks the moment the turret explodes, and then you can simply make your way there. I try to avoid accidentally picking up a rifle since I want the empty slot. Sometimes when the grunt dies, he doesn't drop his rifle.

Revelation: Disturbance
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This stage gifts the player with the almighty Lightning Arc Weapon, or perhaps amusingly, LAW for short. The LAW is by far the most useful weapon in a speedrun as it not only deals outstanding damage, but when aimed above the head of a target, it will lock on to the head of the target, effectively dealing a headshot, making encounters with Nightcrawler Elites throughout the game less variable.

This stage involves two instances of climbing ropes. The one in the beginning saves a few seconds. The one after the hallucination near the end saves around 12 seconds. Normally, ropes are extremely slippery and impossible to climb up, but if you walk from a normal surface onto these ropes, the ropes won't have this slippery property, allowing them to be climbed.

The LAW shows why it is the LAW during Nightcrawler Elite fights. Nightcrawler Elites normally die in two proper headshots with this weapon. I take a certain path through the room initially to make it less likely for the enemies to be alerted to my presence until I begin opening fire. This is because enemies in an 'unaware' state seem to take more damage from attacks for whatever reason. An 'unaware' Nightcrawler Elite can be felled by one LAW bolt, which makes the room substantially easier to clear.

The stage ends with an example of the crouch glitch inside a vent, allowing me to run directly through the vent instead of having to slide through.

There were a few awkward moments in this stage. Some were due to how I was trying to handle the situations I was presented with, but some were simply ugly input errors.

Apprehension: Pacification
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Not a lot to be said about this stage. You basically spend half of it in a cutscene and the other half running across the battlefield to the end. I try to take out friendly soldiers if I feel they are in or are going to be in my direct movement path, but just like enemy soldiers, they sometimes refuse to go down easily.

Apprehension: Bio-Research
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A Leviathan appears in this stage, which is handled pretty easily by a combination of mines and rockets. I have to be careful that I am not too slow in planting the mines, else the Leviathan will strike while I am near them and I will blow myself up. I also have to be careful not to fire my rockets as his are incoming, because if my rockets hit his rockets in midair, the splash damage will likely destroy me. Explosions that I cause will deal about ten times more damage to myself than explosions enemies cause. For example, if an enemy tosses a frag at me, a direct blast will deal around 25 damage, whereas a frag that I toss that explodes within five feet of me will instantly kill me, regardless of my health and armor. I am not sure why every F.E.A.R. game is like that, but that's just how it is.

The second half of the stage is skipped by pressing the elevator switch to leave the stage through a wall. When a right arm punch occurs, it shifts the player forward enough that the elevator can be activated when the prompt briefly appears. As far as I know, the arm the game uses for the punch when it is initiated is random. I discovered this skip three weeks before this run took place and it saves nearly two minutes compared to how I used to play through the second half.

Apprehension: TPC
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This is basically Pacification but in reverse, so there's not a lot to be said about this stage either. It's easier to lose time on this stage in comparison from having enemies in your way. I consider 4+ medkits when leaving this stage to be a comfortable amount.

I used to pick up the Penetrator in this stage, but I figured out that it should be faster to skip it in favor of the rocket launcher for a variety of small reasons. I still pass by it so I can pick up some nearby remote bombs, as the remote has great utility throughout the remainder of the run. It can act as a more reliable melee attack in a number of areas.

The ending is full of shotgun guards, so I pay close attention to my health and I don't let it dip too low before using a medkit.

Devastation: Buried
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The story sequence can only be skipped once Chen begins speaking. I was able to cut in front of Chen before he reached the window, which saves a few seconds. Sometimes the game lets you move that early, sometimes it doesn't. Not sure why.

The LAW is effective against Shades, which can dispose of them in a single headshot. Sometimes killing the first aggros the rest immediately, but in this case it didn't.

Chen's death sequence can't be skipped, but you can skip attempting to pull him out of the Scarecrow void. You can also avoid the Scarecrow afterward by moving past it on the left. Later on, another Scarecrow is avoided by jumping along the side of a wall.

The rest of the stage is spent running from Shades. One of them managed to cut in front of me, which for some reason used to never happen in practice, but started happening in the attempts I had leading up to this run. It was this run that I learned that firing the shotgun to kill the Shade can apparently aggro all of the ones that are at the end of the map... but fortunately, they didn't get in my way nearly as much as they could have. A bit sloppy on my part for not knowing that was possible until this run.

Devastation: The Deep
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The first Scarecrow has to be taken out with two shotgun bursts, but the second can be skipped by simply pressing against the left wall during the jump over.

I have to wait for the water to fully rise before I am able to exit the pool.

I prep a frag then toss it and another one at the grunts near the end. I tried using the shotgun and/or the remote there to get through instead, but they are too unreliable. I dislike having to use frags because if one of the grunts decides to toss a frag at you, you can blow yourself up with your own frags depending on the situation, but the way I do it seems to remove this as an outcome. Taking them out isn't required, but they can deal a lot of damage and potentially block your path if you try to simply pass by them.

Infiltration: Relic
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This stage is over relatively quickly thanks to another instance of out of bounds utilization. Fortunately, it is possible to gain enough height to enter the out of bounds simply by using nearby objects, just like the first stage. Once enough height is gained, you have to clip into the out of bounds by pushing against a specific spot above the pipe. Then, your vertical position must be decreased to move past the wall, but it can't be reduced too much, or else reaching the end level trigger will be made more tedious. Since you can't go under all of the rooms in the way to the exit, you have to go around them, as entering them would put you back within bounds.

Infiltration: Basecamp
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Normally, you're expected to hit a switch to move the train in the middle of the tracks out of the way, but you can squeeze through it instead, which saves around 20 seconds.

I use a mine and the rocket launcher against the grunts after the train. Compared to what I was doing in 2014, it's a much simpler strategy and is potentially faster. The grunt on the left can choose either run into the mine or run away from it, and the far away grunts can do slightly different things as well, but there isn't too much variance overall.

I drop the rocket launcher for the MP-50. You'll see why it is a powerful asset in the next stage.

The area after the checkpoint can be a bit tense depending on how the group of three shotgun grunts position themselves. Together they can deal a tremendous amount of damage if they so choose.

I drop the LAW I currently have, pick up the new one at their 'base', and reobtain the previous one I had. Doing this gives me a fresh LAW with 16 ammo and adds the ammo I had from the previous LAW. If I kept the LAW I had and picked up the fresh one, I would have only been brought up to 16 ammo (8/8) instead of 23 (8/15). It makes the run a bit safer if I have the spare bolts, and costs barely any time.

The trio of Nightcrawler Elites has a bit of variance, but in practice, I'm usually able to kill the trio at around the same speed every time by knowing how to move through the room and when to expect the Nightcrawler Elites to be in favorable positions. Their positions were decent - one of them was in the opposite location I was expecting him to be, but he thankfully climbed up. I even got to collect the fourth's bolts for extra insurance. Killing the fourth is admittedly more for show than speed, although he can sometimes position himself in a manner where you can't get around him through the doorway.

Exploration: Labyrinth
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There are some minor uses of the crouch glitch early on, one of which assists in clipping through part of a container.

It is important to maintain a high health and medkit count as you progress through this stage. If you perform five boosts with the MP-50, you will need a minimum of 71 health and six medkits just to be able to reach the out of bounds entrance, but you'll want more than that left over to ensure future survival.

Extermination: Clone Facility
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There are many medkits throughout the remainder of the run that I can choose to skip depending on how confident I am with my health. Since I entered the stage with one less medkit than normal, I decided to pick up the one in the beginning, since it only costs a couple of frames. If it doesn't matter in the initial part of the stage, where the enemies can deal plenty of damage, it can end up mattering at the end of the game depending on how things go.

I throw a frag across the room in an attempt to manipulate the grunts into more favorable positions. I only ended up needing to use one medkit as a result.

I slide kick through one of the vents because it is difficult to properly crouch glitch into it, and slide kicking is equivalent in speed anyway.

I take a path around the medical area that avoids all Scarecrows. There's a handful of them in this stage and the next stage that are all avoided by clever movement.

I take out a fire extinguisher and an electrical box when I enter the final room. They would deal a lot of damage to me if one of the grunts managed to hit them while I passed by them. If I blow up the fire extinguisher quickly enough in my entry, it will take out the grunt next to it. It simply stunned him this time around.

Extermination: Clone Production
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If you move ahead of Alma while she is active, she will lunge at you. If she touches you, you will instantly die.

I try to make use of the remote bomb after Alma disappears to clear out a path, but when the grunts are too spread out, I just smack the ones in my way with the remote instead.

I acquire a float off of the big ladder during the slowmo effect, which makes acquiring it less difficult, and allows me to float over a Scarecrow that is located next to a canister. I wasn't sure if I got it at first. Sometimes it's difficult to discern between the visuals for when the character is floating and when he isn't floating. The most common visual that indicates that the character is floating is that he will smoothly glide backwards from the ladder after dismounting, but this visual isn't always obvious depending on the situation.

The LAW is the most effective way of dealing with the upper part of the next room due to the presence of the MP-50 guard, since the MP-50 blasts will push me back and the guard can spam them. Afterward, I use the float glitch to descend down an entire section of the stage, effectively skipping part of the stage.

The two Nightcrawler Elites must perish before the upper door is unlocked, which spawns two more Nightcrawler Elites. The Nightcrawler Elite with the grenade launcher can put up the toughest fight due to grenades making the screen shake, which makes hitting him more difficult.

The second pair can be ignored. I wasn't sure if one of them was going to block the doorway, which is why it seemed like I was fumbling around with the LAW, but they thankfully stayed out of the way.

Extermination: Showdown
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I plant mines in the location where the last grunt descends from so that I can break open the ventilation grating and enter the vent right as he dies, since the opening to the vent doesn't open until all enemies that spawn in that room are dead. I decide to take out most of the Nightmares to ensure I have enough health for the end, since the shotgun has close to no impact on movement speed.

The stage ends by performing a corner clip into the side of a construct to gain height. The last portion of the clip is the toughest because of the precision required to gain maximum height from it. If enough height is gained, you won't need MP-50 assistance to reach the top of the construct, and can instead wiggle against the top until it props you up. Once atop the construct, surviving three MP-50 boosts is all it takes to win. Doing so skips all interaction with the Nightcrawler Commander, including his boss battle, as well as the final battle outdoors. I simply have to be careful about how I adjust my height along the way.

The run completes with a glitched version of the ending sequence involving the protagonist and Chen's ghost sitting inside the nonexistent helicopter. Since Raynes is not present, dialogue does not occur.

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Special Thanks

Thanks to Freezard, who figured out most of the ways to apply the float glitch, which by itself caused around a dozen minutes to be saved over the course of the run for this expansion. He also provided additional ideas and assistance in the development of this speedrun.

Bonus Missions

Exclusive to F.E.A.R. Perseus Mandate are the three bonus missions unlocked when you complete the regular campaign. Clinic, Arena, and Sprint are individual levels that are timed to the full second after they are completed.

Bonus Mission 1 - Clinic
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Clinic is the easiest mission to lose time in from being blocked, and has the trickiest ending. Thankfully, you don't have to kill all of the grunts that spawn in the last area to unlock the door and reach the end - only two groups are key. Proxy mines help greatly in taking one of these groups out.

This was a high 1:43 - approximately 1:43.85 if my analysis is accurate. I believe 1:42 is certainly possible, perhaps even 1:41. I took some pretty safe lines to minimize blockage, picked up the health booster, and didn't have as clean of an exit to the stage as I would have liked, so I think grinding out this stage with more risks would eventually yield an improvement, although most of the difficulty to this stage lies in not being hindered by grunts and getting through the window of the medical facility.

Bonus Mission 2 - Arena
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In Arena, enemy spawnpoints are basically not random, but enemies can always choose to act differently or put up a tougher fight. Items that are dropped, as well as the locations in which they are dropped, are also not random, but there's not much you need other than a few medkits to ensure survival against the mechanical enemies, the two deployable turrets for support, and the MP-50 to slaughter the final waves. It is also handy to snag the Particle Weapon from one of the rope grunts. Taking as little recoil from enemy attacks as possible can help speed up the stage. The enemies that deal the most recoil are the Heavy Riot Armor and Powered Armor.

Since the pace is determined primarily on how well the player aims and disposes of enemies, this could theoretically be a few seconds faster, although I am unsure as to how low this could go. My previous personal best for this stage was a 3:36, and at the time, I was only aiming for 3:33, thinking that would be a logical goal, yet I somehow skipped from 3:36 to this time of 3:27 after making a few small changes.

Bonus Mission 3 - Sprint
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Sprint is, as the name suggests, a mad dash to the end of the mission. This was by far the easiest mission to perform in and optimize, and is the most optimized out of the three as a result. There isn't much that can end an attempt at a 1:20 or better, but there are some substantial run-enders. You can occasionally get stuck on objects in the office area where the Unmanned Aerial Vehicles flood in, and can also be blocked by the UAVs. It may be difficult to tell but in the run, I perform a near-instant crouch glitch to squeeze by them, which is usually necessary. The Heavy Riot Armor can inflict tremendous damage, and combined with the group of grunts afterward, surviving to the end is not in the player's favor.

I am uncertain as to whether 1:18 is possible. This run was a 1:19.5 by my analysis, so I am not sure if even tighter movement, more item skipping (such as the group of items before the Heavy Riot Armor), and praying you aren't obliterated as a result of skipping more items, would amount to another half-second saved.