Tetrinet2

Tetrinet2 is a PC based online multiplayer tetromino game, similar to Tetris, available as a free download. t is notable for its 12-block-wide playfield, which is wider than the average tetromino game's playfield, as well as its items, which players can use to attack other players.

This second version of TetriNET introduced piece holding and utilized a single master server where all players connect to, rather than having players host their own servers like in previous versions. The master server has since been shut down due to a cease and desist letter by TTC in 2007.

Game play
TetriNET2 gave the ability to customize the gameplay of matches. Players are able to customize the rules to their liking. Features such as specials, piece holding, and ARE were customizable as well as setting how frequently a tetromino would appear.

Specials
Depending on the game room's settings, a special will appear onto each player's field after every X amount of line clears by that player. Specials can be obtained by clearing their row off the field. If a player clears a special, the amount of that special received into the inventory is multiplied by the amount of lines cleared. For example, clearing a special with a double line clear will yield 2 of those specials into your inventory.

Specials are used in inventory order by pressing the player number you wish to target. Specials can be shuffled at the cost of 1 special by pressing the shuffle inventory key. There are 13 possible specials that can appear:
 * a : Add Line - Adds a line of garbage
 * c : Clear Line - Clears a line from the bottom of the field.
 * b : Clear Special Blocks - Transforms all special blocks into regular blocks.
 * r : Random Blocks Clear - Randomly clears blocks, often making a messier field
 * o : Block Bomb - Only has an effect if the target's field has a Block Bomb special on it. Causes any blocks within a 3x3 radius of those specials to be scattered around their field.
 * q : Blockquake - Shifts the blocks on each row, often making a messier field and giving an earthquake effect.
 * g : Block Gravity - Causes all blocks to pull down to the bottom of the field, and will remove any lines cleared as a result.
 * s : Switch Fields - Switches your field with the target's field.
 * n : Nuke Field - Clears the entire field.
 * Immunity - Makes the target immune from being targetted by specials for X amount of seconds. Default = 15 seconds
 * v : Clear Column - Clears a random column.
 * m : Mutate Pieces - Makes the target's X next pieces large and odd shaped, often forcing the target to make a messier field. Default = 3 next pieces
 * d : Darkness - Turns the target's field black, hiding it from their view except for their current piece and a small window around it for X seconds. Default = 10 seconds
 * f : Confusion - Randomly switches the target's controls for X seconds. Default = 10 seconds