Pulse

About the game

Pulse is an atmospheric, Asteroids-like shooter built around one idea: you cannot see your enemies. Their ships are cloaked, and they only show for an instant when they decloak to attack or when something detects them. The rest of the time you have to find them through your instruments: the sound they make, a long-range radar and a spectrum display that shows signals by frequency and over time, in the manner of a ship's sensor panel.

Your main tool is the scanner pulse. Hold Space to charge it and release it to send a ring of radar into the dark. A small pulse checks the space near you without waking up the arena. A big one reveals contacts far away, but it also tells them where you are, so the signal cuts both ways, as the game's theme, "Signal", suggests. Torpedoes light up a small area as they fly, so even shooting at nothing gives information. Three kinds of enemy hunt you: slow drifters, faster seekers that curve into attack runs, and bursts that dash at you in pulses. Asteroids and meteoroids are always visible, and the world wraps around at the edges.

The sound is part of the game: it is synthesised live, enemy emissions pan across the stereo field by direction and shift in pitch as the ships approach or move away, and intercepted radio bursts show up on the spectrum. Headphones help. It was made by Jed Whitten for Ludum Dare 59.

Playing it here

The game runs in the page and needs a keyboard. Click on it, press Enter on the title screen and play. Your best scores are kept in this browser's local storage. The download is small, about 400 kB. Sound starts after your first key press or click.

Controls

Tips

Start with small pulses. They tell you what is close without calling the whole arena.

Listen as well as look. The panel at the bottom right shows the signal strength by frequency, and the stereo sound shows the direction. Approaching ships shift up in pitch.

Keep your energy up. Shots and pulses spend energy, which recharges over time, and shields recharge faster when the main energy pool is not recharging.

Credits and licence

Pulse was made by Jed Whitten for Ludum Dare 59 and released under the MIT licence. It runs on Phaser 3 (MIT) and uses the fonts Orbitron and Share Tech Mono (SIL Open Font License 1.1). In this version Phaser and the two fonts are served from this site, where the original loaded them from public servers on the internet. The licence texts, the source, the patch and the build script are linked from this page.

FAQ

Nothing is visible on the screen. That is the game: enemies are cloaked. Hold Space, release it, and watch the radar.

Where are my scores kept? In this browser's local storage; there is a local high score table when the game ends.

Is the sound important? Yes. Use headphones if you can: the direction and the pitch of the sounds tell you where the enemies are.