White Noise Online is multiplayer-based Slender-type game, by which I mean it's a horror game where you go around collecting eight randomly placed objects while avoiding a monster that's hunting you. Slenderman isn't actually involved here, and there's some twists to the formula here to keep it interesting, but the baseline is that this is an online co-op Slender-type game, and that fact will either sell you or turn you away from the game.
You play as one of over 20 characters in some very dark environment collecting cassettes. Strange statues line the environments, and a strange glowing monster chases you through the depths of darkness, with an intent to kill. However, the story here is rather non-existent, with the only narrative coming from an opening scene before the title screen, and the audio content that plays on the cassettes themselves when you pick them up.
The cassettes emit a static sound to alert you that they're nearby, which is helpful to the formula as the stages in this game are bigger than most Slender-type games and the monster is notably more aggressive. One feature kind of cool and creepy about the monster is that he makes appropriately unnerving sounds to both sort of alert you where he is, and unnerve you. It can be creepy to be in a tight-corridor area and not see him, but it sounds like he's right next to you. Staring at the monster will slowly deplete your 'health', and he'll kill you if you let him get too close to you. There are also green-glowing statues placed around the environment randomly, and staring at them or getting too close will have the same effects the monster has (though of course the statues can't move). The statues emit a static-sound similar to the cassettes (though different enough to tell) to lead players to a tricky end.
There are four difficulty levels, which mostly determine the difficulty of the monster, how many statues there are, and cassette placement possibility.
The game also has a panic-system that's kind of similar to what you'll find in Clock Tower 3 or Haunting Ground. When you are isolated and alone, your character will start panicking (which can be noted when the character starts making panicked sounds and the screen starts acting up), and eventually starts tripping all over the place and making a lot of noise, which attracts the monster. This can be settled by either collecting cassettes, or finding other people.
How prone they are to this depends on what character you play as. There are over 20 different characters, and they all have different stats. These are represented by an image for each 'category' (the images can be confusing at first, can read up on what each one means in the How to Play section on the options menu), with a notice of if they're stronger or weaker in this area than other characters (represented by a +1 to +3, or a -1 to -3, if not shown then they are neutral, or default, in that area). Areas effected include sanity (take less damage from the monsters attacks), flashlight battery life (the longer you keep your flashlight on, the more it will flicker and start becoming dimmer and dimmer), movement speed, stamina (for running), scout (the further distance you can get from characters before panicking), evasion (how high you are on the monsters priority list), and more. You only start with four characters, while the other ones are unlocked by playing the game and accomplishing tasks.
There's also some fun multiplayer mechanics that are rather well thought-out. Firstly, death. When a player dies, they then become a ghost, which is visible to the living players as a blue silhouette of the character that died. The ghosts can stick around the living players to help prevent them from panicking, or they can go out and scout for cassettes. The ghosts see the level much more brightly than the living do, and they also move a lot faster around the level. However, they cannot see the monster, but can spot cassettes. This can be helpful in downtime and to be helpful even after death. The second feature cool for multiplayer is the results screen, which displays fun information like the total distance each person walked, number of cassettes each individual collected, how many times they were hit by a scare attack and 'screamed', how long they survived, etc., along with a map that shows the routes that each player took during the course of the game.
The game currently has six maps, though the devs have noted if it does well they plan to add more. The maps are fairly varied, with themes like tropical island, government base, museum, snowy forest, and the like. There are three different map 'styles', with two maps under each style. The first is big-open levels that have monuments, like the original Slender. The second are closed-spaces interior maps with twisting corridors, rooms, and labyrinth-like structures. The final are 'island' stages, which has parts of levels connected with tunnels, bridges, and the like, with the level segments being separated like islands.
This game was an Xbox Live release originally, the main difference in the Steam version right now is that all characters are now unlockable (as opposed to some characters only obtainable by owning other games), achievements, and they've updated the graphics some. This said, more updates may arise in the future to further differentiate it.
In short, it's a very confident Slender game, actually one of my favorites. The online multiplayer is fun and well-thought out, and the game still manages to be tense and scary at times. If you like Slender-based games and have wanted or are interested in trying a multiplayer-based version of that type of game, this is it. There really isn't any better, and the game does very well at what it sets out to do. However, if you don't enjoy Slender-type games, or the multiplayer focus doesn't interest you, this probably won't interest you. The game maybe works better in short bursts than long marathons, but it's still a fun little multiplayer horror game.