Receiver is an INCREDIBLY challenging game. You will hate it and love it at the same time.
You play an unnamed protagonist navigating through various indoor and outdoor areas in a structure located in an unnamed city. Many of the rooms are guarded by randomly-placed sentry turrets that shot you on sight, or helicopter/taser sentries that fly at you when you are detected.
You come armed with one of three different handguns, all of which are nicely-rendered. Each one is operated in a realistic-manner that may be off--putting to the gamer used to relading by simply pressing the R key. In this game, reloading could involve five distinctly-different operations, depending on the gun you happen to have on you at the time. The sound effects of the guns are nice, and have an authentic feel to them.
The environments you travel around in are randomly assembled, and comprised of flat-shaded textures and occasional lights. The assembly of the rooms means that you occasionally find passages to nowhere, but that doesn't really detract from gameplay. Repetition is high, and some of the rooms/areas are confusing, but since you are just passing through, it's not really a big deal. Your goal is to locate ammo and tapes, and the threats are there to stop you.
Audio is pretty good, with a couple of notable exceptions:
1: the helicopter sentries are loud enough to be heard from one room over, but it becomes difficult to pin down their locations based on the audio alone.
2: The sentry turrets also make sounds while they rotate, but you can't hear them until you're almost right on top of them. Their sounds, as well as the helicopters, also pass through walls/floors at the same volume level. This aspect of the game is bothersome if you are searching a room. I prefer to play the game with the music silenced so I can try to hear the threats before they spot me, and often I find that I am shot dead before ever hearing the servo motor of the turret that nailed me.
3: The audio tapes are well-voiced, but remind me a lot of the sort of thing you might find on a webiste run by fringe-science/conspiracy theorists. After playing for a few hours, I completly silenced the tapes because I became bothered at having to hear them over and over again. Kudos to the devs for allowing this option in the settings.
The main goal of the game is to find all 11 tapes, and "absorb" them by listening. Listening occurs while you continue exploring, so that's a good thing. I did find a couple of small problems with the exploration/survival aspect:
1: Sometimes the game allows you to access an area that does not have an exit. The only option is to exit and restart.
2: You are assigned a random firearm and random loadout upon starting. Rarely, you will find yourself without enough ammo to eliminate enough of the threats to be able to find more.
3: (Extremely rare) you begin the game in the direct line of site of a threat, and get killed immediately.
For a game created in a week as part of a contest, the developers have done an admirable job! The simplicity of the design and the addictiveness of the concept keeps me coming back over and over again. I've only managed to get as high as 4 tapes before being mowed down by a threat in a moment of complacency. The game forces you to be on high-alert at all times, and punishes relaxed attitudes brutally. You will learn to use expletives effectively, I guarantee.
Worth every bit of the 5 bucks it currently is. Get it. You'll be glad you did.