Infinite possibilities of combat in a unique environment.
The game now contains what I think is eight maps, but I never decided to count them. What matters is that they're huge, and can be played in three incredibly fun gametypes with multiple routes to each objective. I had assumed it would simply be a Quake 3 deathmatch style game set in zero-G, but was massively wrong. With massive maps and zero gravity comes massive tactical multiplayer gaming.
Now, many games claim to be realism shooters or something of the sort, but simply end up either being extremely simple versions of "realism" (no leaning and cheap ballistics and the like, maybe some cover system gimmick) or tedious games that claim realism by adding a bunch of tedious micromanagement to do, ending up killing any fun I've had in them, as well as a multitude of bugs. Believe me when I say that Shattered Horizon does not try to be realistic (though I can't say I know exactly how realistic it is compared to the imagined space combat), but rather tactical.
There is a huge difference between realism and tactics. Realism refers to how firing from the hip compares to firing while aiming down sights and how long you can run before dropping dead from carrying fifty pounds of weaponry on your back. Tactics refer to how enemies have you on their radar, and it is up to you to decide whether to hurl an EMP at them to disable their heads-up display and charge at them, or to hold your ground in order to try to defend your control point, or to turn your own suit off (along with your own heads-up display and ammo counter) and hide in the shadows, waiting to ambush them.
There are nearly limitless possibilities to happen in the game and with recently added voice communication teammates are better enabled to plan together amongst one another.
I will personally vouch for the fact that the game comes with one gun. That does not mean, however, that it comes with one weapon. Said gun is by default an automatic rifle, carrying a magazine of sixty rounds, with an unlimited supply of ammunition. Zoom in and it becomes a high-powered sniper rifle, using ten of the sixty bullets in a magazine for each shot. The rifle also has a supply of four grenades which have three different configurations: the spicy EMP grenade, shutting down the receiver's suit momentarily; the MPR grenade, exploding into bits, exploiting zero gravity as it shoves all recipients forcefully into outer space; and the ice grenade, used to deploy what is basically interchangeably either a smokescreen to confuse enemies inside, or cover to keep them from knowing where in that cloud you are. There is also a very useful melee bayonet that can be utilized for silent kills, which helps a lot with the stealth aspect of the game.
In technical terms, Shattered Horizon is amazing as well. It is, hands down, the best looking video game to date, defeating, in both detail and style, any PC exclusive such as Crysis or any console exclusive such as Uncharted 2 (which is actually poor in a sense when looking at details the player is veered away from looking at). Lighting is amazing, as HDR rendering is well-implemented so that the sun creates a massive bloom that darkens the rest of your vision and refracts across the screen and such. As space has to be, everything is fantastically shiny, with a nice color scheme. Damage to the environments is well-rendered and looks like fit really hit the shan when asteroids hit the ISS. All textures look really good and the lighting is amazingly vibrant, even in darker areas. No one runs in space or anything, so real human animation is found few and far between, but what is there, such as walking on a surface, is well-done.
Sound is also very good, as your suit picks up some signals or something and translates them into sounds of gunfire or whatever else for the player's tactical convenience. All the sounds are very meaty and shiny at the same time, and powering down only to hear my own breathing apparatus and nothing else is one of the most tense things I've experienced in an FPS.
The one thing that could possibly keep a person from wanting to buy Shattered Horizon, rather than being a singleplayer only gamer, is the requirements. The player needs a DirectX 10-compatible card and Windows Vista or Windows 7. The developers only needed to sacrifice a few sacred cows to make it much more compatible with older systems, but they are from a company that previously made only programs that yelled at your computer for being too slow, so they're probably used to be snooty about graphics. However, you'd not expect a bunch of graphics whores to make an overall amazing game.
They did.