TETR.IO

TETR.IO is an online browser game made by osk (as in ki-osk) currently in alpha development. It mainly features competitive one-on-one gameplay with a limited set of singleplayer modes. There are 4 singleplayer modes (Sprint, Blitz, Zen, and Custom) and 3 multiplayer modes (Quick Play, Custom Rooms, and Tetra League). It was originally in INDEV on Feburary 19, 2019, went INFDEV on January 31st, 2020, and went Alpha on March 22nd, 2020.

TETR.IO differs from most other games with things such as a standard "change on attack or change per attack" attacking system, a new attack table with a "multiplier" system, adjustable tuning along with Soft Drop Factor and DAS Canceling Delay settings, etc.

Singleplayer Modes
Singleplayer has 4 modes, which are Sprint, Blitz, Zen, and Custom. A 5th one was available for a limited time, called "5,000,000 Blast", to celebrate the game reaching 5 million registered members.

Sprint
Sprint is a mode where players are tasked to clear 40 lines in the fastest time they can. While nothing new, you can do specific tasks in this game mode to unlock 3 Badges.

These tasks are:

Secret Grade: Complete the Secret Grade pattern and you will be awarded the Secret Grade badge.

20TSD: Clear 40 lines using 20 T-Spin Doubles. Doing this will award you the 20TSD badge.

10 PCs: Make 10 Perfect Clears in Sprint. Not all PCs need to be 4 line. There just needs to be 10 PCs in the run in order for you to get the 10 Perfect Clears badge.

Note that Secret Grade is not specific to 40 Lines and can be cleared in any singleplayer mode except Zen.

Blitz
Blitz is a 2 minute score attack run, similar to Ultra gamemodes in most other modern games. In TETR.IO, Blitz has a twist in having a leveling system that not only multiplies one's score points but also increases gravity with each level passed, similar to the standard Marathon modes in all of the modern Tetris games. It takes 3 lines to get to level 2, 5 lines to level 3, etc. Oddly, at level 11, the goal to level up (to level 12) increases by 3, (24) but then returns to the basic +2 format. (Level 12 to Level 13 would take 26 lines)

Similar to other score attacks, Perfect Clears award a large amount of points. The score chart for each action is shown below:

Unaffected by the level multiplier, Soft Drop gives you 1 point per cell dropped and Hard Drop gives you 2 points per cell dropped.

Zen
In Zen, the player can choose between many settings in the Zen menu. It contains a levelling system similar to one of Bejeweled's modes. Players can easily set settings through the sidebar and change settings like gravity, cheese, payback garbage, rotation and spin systems, etc.

Custom
In custom, the player can specify even more settings than Zen, such as board size, rotation, etc. Usually used just for fun. (You can press Ctrl-Z to undo and Ctrl-X to redo)

Multiplayer Modes
In TETR.IO, there are 3 types of multiplayer modes; TETRA LEAGUE, QUICK PLAY and CUSTOM ROOM.

Combo System
TETR.IO's combo system uses a logarithmic scaling exclusively for single combo line clears to nerf 4-wide strategies, but also buffs big attacks the longer a combo goes.



Back-to-Back Chaining(B2B)
To take advantage of this mechanic, one must preform several "difficult line clears", meaning Quads and T-Spins, without clearing singles, doubles, or triples in between each difficult line clear. This is known as a Back-to-Back, and they are rewarded in other Tetris games and clones by adding one line of garbage to an attack.

TETR.IO takes this idea one step further, and rewards the player according to how many Back-To-Back line clears one can clear in a row:

Tetra League
When a player achieves level 10, they can play TETRA LEAGUE. Anonymous players cannot play this mode. Each game of TETRA LEAGUE is a 1v1 match, with a FT3(First To 3), FT5(First To 5) or FT7(First To 7) format based on one of the players' rank. The rating system is called Tetra Rating (TR), which is based on Glicko-2. TR increases for each win and decreases for each loss exclusively. When playing this mode for the first time, the player must play at least 10 ranked matches, referred to as the "rating games", to display their TR. A letter rank is assigned to all players with less than 100 RD (short for Rating Deviation) based on their percentile in the leaderboards. RD normally decreases to a lower limit of 58 RD every time the player plays a TETRA LEAGUE game, and slowly increases at a flat rate of 1 RD per day after a week of inactivity, leading to a maximum of 350 RD.



^ The Ranks look likes this ^

Quick Play
Quick Play is a public FFA room. When the room’s number of players exceeds 100, Super Lobby Mode will be engaged, a reference to the Hard Drop Super Lobby community events beginning in October 2019 on Tetris 99. The winner achieves a Badge called Emerged victorious in a 100+ player game. This also applies to custom rooms.

Custom Rooms
Players can create a public or private room. A Room ID consisting of 4 alphanumeric characters is generated after room creation, which can be shared to other players to join that room.

Public rooms can be accessed through ROOM LISTING. Private rooms can be accessed either by entering a Room ID or an invitation from a friend.

One can change many settings in a custom room. These include the spin system, the passthrough modes (passthrough is when, due to network delays, attacks will literally ‘pass through’ each other), the garbage multiplier, the gravity, and more.

Trivia
If a player KO's or gets KO'ed by osk, they can receive these multiplayer Badges:

KO by TETR.IO Founder: KO osk in any gamemode

KO'd by TETR.IO Founder: Get KO'ed by osk in any gamemode