Battle Guide

Tetromino Arcade supports two-player score battles across two browsers or on one shared device. Both formats begin from the same piece seed so the comparison starts with matching piece order, while every move and board decision remains the player's own.

Choose A Battle Format

• Online Friend Battle: two browsers connect through an eight-character room code. Both players mark Ready before the shared start.
• Same-Device Battle: two Marathon boards open side by side on one device and use separate sections of the same keyboard. No room code is needed.

Start An Online Friend Battle

1. Open the game and choose the Battle button with the crossed-swords icon. Enter a short display name, or leave the default Player name.
2. The host chooses Create Room. The game connects and shows an eight-character room code.
3. Share the code, or choose Copy Invite to copy a link containing the code. The invitation opens the Battle panel with the code filled in; the invited player still chooses Join Room to connect.
4. Wait until both player names appear. Each player chooses Ready. Choosing the button again before the round begins cancels that player's ready state.
5. When exactly two connected players are ready, the server schedules both level 1 Marathon boards to start from the same seed.
6. During the round, the battle strip shares each player's display name, score, lines, level, and current game status. Use the two scores for the casual comparison.

Online Controls

Online battle uses the regular single-board controls:

• Left and Right arrows move the active piece.
• Down arrow soft drops; Space hard drops.
• Up arrow or X rotates clockwise; Z rotates counterclockwise; A rotates 180 degrees.
• C or Shift holds the current piece.

On phones and tablets, the buttons below the board provide movement, both rotation directions, soft drop, hard drop, and hold. Board gestures also work: tap the right side to rotate clockwise, tap the left side to rotate counterclockwise, swipe sideways to move, swipe down to hard drop, and swipe up to hold.

Start A Same-Device Battle

1. Open Battle and choose Same Device Battle.
2. The split-screen round starts two level 1 Marathon boards with one shared seed.
3. Sit one player on each side of the keyboard and use the separate key sets below.
4. The shared status shows who leads and by how many points. After both boards finish, the higher score wins; equal scores produce a tie.

Same-Device Controls

Left player:

• A and D move left and right.
• S soft drops; W hard drops.
• Q rotates counterclockwise; E rotates clockwise.
• F holds the current piece.

Right player:

• J and L move left and right.
• K soft drops; I hard drops.
• U rotates counterclockwise; O rotates clockwise.
• Semicolon holds the current piece.

The shared Pause control pauses both boards when they can be paused. New Round resets both boards with a new shared seed, and Exit closes split-screen battle.

What Same Seed Means

The game's piece generator is deterministic. In each battle, both engines receive the same seed, mode, and starting level, so they draw from the same generated piece sequence. A player who consumes the same number of pieces as the other player receives the same pieces in the same order.

Same seed does not mirror inputs or board state. Movement, rotation, hard-drop distance, hold use, T-spins, line clears, mistakes, and top-out remain independent. Using hold can also make the two visible queues look different at a particular moment because the players may have consumed different numbers of pieces. The fairness guarantee is the common starting sequence, not identical play.

The format compares points earned under the shared scoring rules. It does not turn one player's board into a copy of the other player's board.

Reconnect After A Connection Closes

If an online socket closes unexpectedly, the Battle panel keeps the current room code and enables Reconnect. Open the panel, confirm the name, and choose Reconnect to try joining that same room again. The active room code may also be remembered temporarily in that browser session so a reload can reopen the Battle panel and attempt the same room.

Reconnecting works only while that room still exists and has an open player slot. A room no longer exists after its last connected player is gone, and reconnecting is not a promise to restore every detail of an interrupted round. If the game reports that no room was found, have one player create a new room and begin a new round.

Room-Code Troubleshooting

• The code is rejected before connecting: enter exactly eight letters or numbers. A single hyphen after the first four characters is accepted, and lowercase is changed to uppercase.
• No room was found: check every character. The host may have left, both connections may have closed, or the code may belong to an old room. Create a fresh room if the code still fails.
• The room is full: online rooms allow two active players. Make a new code rather than repeatedly joining the full room.
• The invite opens but nothing starts: the invited player must choose Join Room, then both players must choose Ready.
• The room waits with two players: look at each ready label. The round starts only after both connected players are marked Ready.
• The connection fails: check that both browsers are online, reopen the Battle panel, and try Reconnect. If the service asks you to wait before creating more battle connections, pause briefly before trying again.
• A friend leaves during play: the remaining player sees that the friend left. Use a new room when both players are ready to restart cleanly.

Battle Privacy

No Tetromino Arcade account is required. The browser may save the optional battle display name locally. It may keep the current room code or a pending invitation code temporarily in session storage for navigation and reconnect behavior.

Online battle sends the display name, room code, ready state, score, lines, level, mode, and game status through the battle service so both players can see the match. Connections use HTTPS or secure WebSockets on the published site. Do not put a real name, phone number, address, account ID, or other contact information in a display name. Names are filtered and limited to 18 characters.

Share a room code only with the friend you intend to play. It is a temporary route into a two-player room, not an account password or proof of identity. The Privacy Policy lists the browser and battle data in more detail.

Casual And Non-Prize Limits

Online stats are shared to support a friendly live comparison. The game does not present a battle as a verified esports result, cash contest, official ranking, or server-refereed tournament. Display names do not verify identity, and the same-seed start does not guarantee that two people will play for the same length of time or make equally fast inputs.

There is no built-in entry fee, prize, payout, betting, or wagering flow. Any outside offer involving money or prizes is not part of Tetromino Arcade. Use the mode for ordinary friend play and follow the site's Terms.