Take turns placing X and O. Get four of yours in a straight line: along a row or column, up through the layers, or diagonally through the cube. There are 76 lines.
Point at a cell to light up the cells above and below it. Drag anywhere around the tower to turn it. Reset angle turns it back.
The keypad places a mark by coordinates: tap the layer, row and column, then Place. Until you tap a number, it shows the last move. Hide board shows the keypad only. Hide history shows only the last mark until the game ends. Hide coordinates keeps the numbers of the last move off the keypad, so you follow the game by its sounds.
Every cell has its own sound, so you can follow a game by ear. The speaker button turns the sound on and off. The arrow next to it opens the sound sets, and each set tells its map in the menu. In the default set, Cells, the pitch is the layer: higher layers sound higher. The instrument is the row: 1 a wooden marimba, 2 a glass bell, 3 a plucked string, 4 a soft whistle. The width is the column: 1 is one thin voice, then a fifth joins, then an octave, and 4 has both. On headphones the column also comes from the left (1) to the right (4). O sounds one octave below X. The speaker button by the keypad plays the last move again, or the cell you typed.
The microphone button next to the sound control turns play by voice on. On your turn, whistle, hum or sing: the cell of your pitch shows as the aim, on the board and on the keypad. Hold the note on a free cell for 1 second to place your move. The voice pauses while the game plays a sound and on the other player's turn, so the speaker does not feed the microphone. The range is the one of /sound-input, so calibrate there to fit your voice. With Hide board and the cell sounds, you play without eyes and hands.
The Song button on the result card plays the finished game as a melody, one note per move. Hold it, or right-click it, to share the song as a sound file. Where the browser cannot share files, the file downloads.
Time limits work like a chess clock. Set a limit for each player's whole game, a limit per move, or both. A player who runs out of either limit loses. The first move of each player is untimed. A change during a game starts with the next game. A timed game has no undo.
Lock stops setting changes until the game ends: the difficulty, the time limit, the hide options and the view. A reload does not end the lock. You can still leave the game. The theme, the sound, the sound set and play by voice stay free. Online and in Nearby, the lock and the hide options apply to both players, and a lock waits for the second player. Watchers cannot lock.
Hover or long-press an icon button to see what it does.
Online, share the code, the link or the QR code. A friend joins with the code in the Online mode, or opens the link. Nearby plays with devices on the same Wi-Fi: one device hosts, the others join. With another device, moves are final and a new game starts after the game ends.
My games lists the games of this session with Replay and the result card, your history, and your sessions.