Space Beast Terror Fright
Game: Space Beast Terror Fright
Strongly recommended! An intense and scary single/multiplayer horror/sci-fi FPS, with procedural levels. What people thought the Space Hulk/Colonial Marines games were going to be. Almost impossible singleplayer, but good with a group. Make sure you have at least one friend before buying.
THE LONG VERSION
A deceptively slow-paced and extremely tense game that places you as a space marine in huge, powered armor and puts you on randomly generated ships to download cores for... some reason, or rescue very fragile civilians.
That may sound standard or identical to other Space Hulk-esque games, but I assure you the execution is unmatched by anything else.
You see, your suit has limited ammo, vision, and power, but you don't notice that before the game starts cranking the stress-o-meter to 15 out of 10. When your enemies actually bother to show up, it's horribly disorienting (in a good, atmospheric way), and is pretty much guaranteed to make you dookie a shooter straight out through your pants and chair.
Note that "disorienting" does not mean "incomprehensible". You have a motion sensor, a flashlight, and even a rangefinder counting down the meters before your face eaten off - You'll always know what killed you, it's just a lot faster than you might be used to.
Also worth noting is that you are very vulnerable in this game. It is not a power fantasy, and a great example of how having weapons and the ability to defend yourself does not necessarily remove the horror element from a horror game. You don't move that fast and have limited room to maneuver. Friendly fire is always on and it doesn't take many rounds to kill a teammate. When guns fire, their muzzle flash can be blinding and disorienting, turning dark hallways into panicked strobe-lit dancefloors of death. In case you weren't stressed out enough, your character's heart rate increases as the enemies close in, represented by the screen pulsating in time with the heart rate. This game is not for epileptics. At all. The menu says it best: "This game will melt your face off".
On top of all that, your enemies - the titular "Space beasts" - are very fast and instantly lethal in melee range. They're as deadly as their name is stupid: instant death in melee, able to smash doors, they come out of the goddamned walls, they turn off the power as much as possible, and they do it all at blinding speed. Even with turrets, a full load of ammo, and experienced team members, you are in a race against time to do your job before they overwhelm and kill you.
On top of THAT, there's an equally stupidly named enemy type called the "Astro-Creep". they both scare the♥♥♥♥♥♥out of you by face hugging your helmet and obscuring your vision, and also help result in about 3000% more friendly fire incidents by setting off automated turrets, smartguns, and motion sensors that don't realize they're actually very small wall-crawlers.
All you need to do to get out of this hellhole is accomplish your objectives as quickly as possible and get back to the shuttle. Seemingly impossible at first, but if you use turrets, make good use of locked doors and laser walls, and get a good teammate or two, you have a chance. You also get random upgrades like aim assist or infravision when you accomplish objectives like downloading cores. The upgrades really stack up over time, so doing the job quickly is very helpful. Sentry turrets can be activated to help you out. Naturally, they will shoot and kill you if you stupidly block their line of fire between you and an alien. There are also ammo and repair bays scattered randomly on the map. Tough, but fair.
Note that while you can play by yourself, you will almost certainly fail all but the smallest ships. You really need at least one other person to play with you to have a realistic chance to succeed. Strongly recommended, nevertheless.