How to Play Retro Arcade Shooter - Step by Step
The Retro Arcade Shooter page loads Underrun in a same-origin iframe (~120 KB). Clear a dark underground server facility: WASD to move, mouse to aim, hold click to fire, and reboot every CPU to open the next of three levels. Press Play to start.
Step 1 - press Play on this page
Press Play to inject the iframe (readable Underrun source + PNG level maps + texture atlas). The launch panel notes the coarse-pointer limit. The game is Underrun by Dominic Szablewski (MIT); music by Andreas Loesch; LICENSE and credits ship beside the files.
Step 2 - unlock audio and start level 1
Click once in the game canvas to unlock audio (Sonant-X synthesizes music and SFX in the tab - no audio file downloads). Terminal-style boot text appears; then you spawn in level 1.
Step 3 - move, aim, and fire
WASD or arrow keys move. Mouse aims. Hold left click to fire plasma (per-shot cooldown while held). Spider robots swarm melee; sentry turrets shoot projectiles. Grab health packs when they drop.
Step 4 - reboot every CPU
Each level has a CPU count you must reboot to open the exit. Finish all three levels (maps loaded from tiny PNG images). On death the level auto-reloads after about three seconds - runs stay short.
Step 5 - what this page does not do
No saves, scores, accounts, or leaderboards. No touch or gamepad. One plasma gun, no upgrades. Exactly three levels - not procedural. This is a tilted top-down view, not a first-person shooter (see Retro FPS Online for that).
| Setting | Value | Notes |
|---|---|---|
| Download | ~120 KB | Same-origin iframe; zero network after load |
| Renderer | WebGL 320x180 | Pixelated upscale; needs WebGL |
| Input | Keyboard + mouse | No touch; no gamepad |
| Levels | 3 | PNG maps; reboot CPUs to advance |
| Saves | None | Nothing written to browser storage |
See when to play, comparisons, and Chili Blast Shooter.
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