Signal

by bitPOD

A one-button arcade game about binary.

What it is

Signal is a small game you can play in a minute. A stream of bits, zeros and ones, flows in from the right of the screen. Your pod holds a bit of its own. Tap, click or press space to flip it. When a bit reaches you and matches yours, you catch it. When it doesn't, the letter it belonged to is glitched and the signal weakens. Three glitched letters and the run is over.

The bits aren't random. Every eight of them spell one letter of a hidden message in plain ASCII, most significant bit first, and the line above the play area fills in as you decode it. Catch a whole letter cleanly and it appears. Miss one bit and that letter comes out as a glitch, and costs one life however many of its bits you then miss, though each further miss in it speeds the stream up a little until the letter is over. Finish a message and the next one starts, a little faster.

Mistakes aren't final. Decode a whole word with every letter clean and you win a life back, and the earliest glitched letter in the message is wiped blank. When the message reaches its end, any blank letters come round again in the stream for another go, and a message with nothing left glitched counts as perfect.

How to play well

• Watch two or three bits ahead. The stream is visible, so you can plan your flips.
• Runs of the same bit need no input at all. Rest during them.
• Capital letters in ASCII all start with 01, so the first two bits of every letter are a free pattern once you know it.
• The letter forming at the top is what the bits so far spell, with the bits still to come taken as zero. A capital letter starts as a dot, becomes @ once its 01 is in, and climbs from there.
• A space in the message costs nothing. It reveals itself.
• Pause with the button in the corner of the play area, or the escape key. From there you can carry on or leave for the title, though leaving ends the run.

Three levels

Pick one on the title screen. Hard is the game at full pace and full points. Normal and Easy start slower and speed up more gently, and pay three quarters and half the points for everything, so a score means the same thing whichever you play. The letter beside a name in the high-score table says which level the score was set on.

Scoring

One point per bit caught and ten for a letter decoded without a miss. A word decoded with every letter clean scores ten per letter, multiplied by your run of clean words: the multiplier rides on your pod and starts at one, and each clean word pays at the multiplier shown and then raises it. A ring of charge appears around the pod for every clean word, violet then magenta then white as the run lasts. Any glitch shatters them and breaks it back to one. Then a bonus for each message completed, bigger when it's perfect. Your scores are kept in your browser, and the ones you put initials to go on the world table too, which you'll find under scores on the title screen.

Who made it

The music is not a recording. It is sixteen bars of note data that your browser turns into sound as the page loads, using ZzFXM by Keith Clark, built on ZzFX by Frank Force. Both are open source under the MIT licence. The loop speeds up as the stream does, which is why it climbs in pitch when things get hard.

Signal was made for fun and runs entirely in your browser. There are no accounts, nothing to install and nothing to buy. If it's slow or broken on your device, or you just want to say hello, write to info@thinkpod.net.