Tetreml

Tetris written with pure HTML and JavaScript.

Play it

Singleplayer
Two-player
Sandbox

Tools

Singleplayer replay viewer
Singleplayer replay analyzer (40-line only)
Customize
Fumen to GIF generator

Note: This game only works with Chromium browsers (Google Chrome, Microsoft Edge,...) and Firefox. Please use one of those to play.

How to play

Basics

The game happens in a "machine" called Tetrion. You try to drop pieces, called tetriminoes, into it such that they form a continuous line from the Tetrion's left edge to the right, in which case they disappear. But don't let the tetriminoes stack too high, the machine will overflow and it'll be Game over.

Each tetrimino entering the machine falls naturally, at the speed that gets faster and faster as you play. If it cannot fall further into the machine for some time, it locks in place and the next tetrimino enters the Tetrion.

To maneuver the falling tetrimino, there are these buttons:

The NEXT box allows you to see which tetriminoes are waiting to enter the Tetrion, so you can plan ahead and score more points.

The HOLD box can store one tetrimino for use later. By pressing the Hold button you can send the current tetrimino there and take the tetrimino that was previously in the box, putting it into the Tetrion again. If there is nothing in the HOLD box, the NEXT piece will enter the machine instead.

Scoring

You receive points when you lock a tetrimino, when you clear lines, or when you do special things. Tetreml has two scoring systems in place:

Tengen-like

Locking

When you lock a tetrimino, the higher it is, or the higher the level, the more points you receive, up to 1000 each tetrimino.

Clearing lines

Normally, when you lock a tetrimino, you receive additional points for number of lines you clear after doing so:

Combo

If you clear lines consecutively, you are creating what's called a combo and you will be awarded additional points of 50 . (number of consecutive clearings – 1). For example, if this is the 4th consecutive tetrimino that clears lines, you will get 50(4–1) = 150 points.

T-spin

If you manage to rotate the T tetrimino such that it jumps in a specific way (usually into a tight slot), it's called a T-spin. The amount of points you receive depends on the number of lines cleared and the judgement of the spin itself, overriding the Clearing lines section above:

Back-to-back

If you manage to get consecutive Tetrises, T-spin mini doubles or T-spins at least single, it's called Back-to-back, and the amount of points you receive from clearing the lines will be increased by 50%.

All clear

If you clear the lines such that the Tetrion becomes empty, it's an All clear, and you get 1000 points.

Guideline

Dropping

When you soft or hard drop a tetrimino, you receive 1 point for each block soft dropped, and 2 points for each block hard dropped.

Clearing lines

Normally, when you lock a tetrimino, you receive additional points for number of lines you clear after doing so:

Combo

If you clear lines consecutively, you are creating what's called a combo and you will be awarded additional points of 50 . (number of consecutive clearings – 1) . level. For example, if this is the 4th consecutive tetrimino that clears lines at level 6, you will get 50(4–1).6 = 900 points.

T-spin

If you manage to rotate the T tetrimino such that it jumps in a specific way (usually into a tight slot), it's called a T-spin. The amount of points you receive depends on the number of lines cleared and the judgement of the spin itself, overriding the Clearing lines section above:

Back-to-back

If you manage to get consecutive Tetrises, T-spin mini doubles or T-spins at least single, it's called Back-to-back, and the amount of points you receive from clearing the lines will be increased by 50%.

All clear

If you clear the lines such that the Tetrion becomes empty, it's an All clear, and you get 1000 points.

Some technical things for nerds

Lock delay

When the tetrimino realizes it cannot fall anymore, it will wait for a small while before deciding to lock into place. If you successfully rotate it, the timer will reset. However, you can only rotate a number of times until that no longer works, but if the tetrimino falls further, you can rotate it to reset the timer again.

Clear delay

After lines are cleared, the Tetrion pauses for a brief moment before letting a new tetrimino enter. The amount of time is half a second most of the time, but it is a full second when you level up in singleplayer or get an All clear.

Auto-repeat

When you hold down the Move left or Move right button, after an amount of time called Auto repeat delay, the game will continue to move the tetrimino every interval known as Auto repeat period. These can be adjusted in the Game options.

Player versus player (PvP)

The two-player version is essentially a PvP game: the two battle until one gets their Tetrion full and eliminated. There are special mechanics in this version:

Global level

When a player clears lines, the number of lines cleared gets added to a total of both players and is used to calculate the level, thus falling speed, of both players. Thus, if your opponent is slow, you can still boost it fast yourself.

Garbage

If a player clears lines, makes a combo or other things, they can send garbage lines to the opponent which push stuff in the opponent's Tetrion upwards. Each Tetrion has a gauge displaying garbage the opponent has sent waiting to be deployed. When they appear, don't be panic yet, there is a delay before they actually get inside the Tetrion, and you can do the same as attacking to negate them.

Game controls

Game controls are viewable and customizable in each game mode. An exception is the sandbox whose controls derive from singleplayer, thus changing singleplayer controls also changes the sandbox's.

Resource packs

Some resource packs for Tetreml can be downloaded here. They can be applied via the customizer.

Data privacy

Currently, Tetreml doesn't send your data anywhere. All data: high score, controls and other configurations are stored locally on your computer. This may change in the future as new features are added. If you are concerned, you can keep an eye on this section for latest updates.

Issues

If you encounter bugs or have some improvement suggestions in mind you can report them on the GitHub repository.