<!doctype html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1"><title>IRON ABYSS – retro FPS in PHP, play free online</title><meta name="description" content="IRON ABYSS: a 90s retro first-person shooter written in PHP, free to play in your browser. A software BSP renderer ported from the 1993 GPL source, original monsters, weapons and levels."><link rel="canonical" href="https://{{DOMAIN}}/en/"><link rel="alternate" hreflang="fr" href="https://{{DOMAIN}}/"><link rel="alternate" hreflang="en" href="https://{{DOMAIN}}/en/"><link rel="alternate" hreflang="x-default" href="https://{{DOMAIN}}/"><link rel="icon" type="image/png" href="../images/favicon.png"><meta property="og:type" content="website"><meta property="og:title" content="IRON ABYSS – retro FPS in PHP, play free online"><meta property="og:description" content="IRON ABYSS: a 90s retro first-person shooter written in PHP, free to play in your browser. 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It runs in your browser.</p><a class="play" href="../play/">▶ PLAY NOW</a><p class="small">Free, nothing to install, keyboard or gamepad.</p></div></header><main class="wrap"><section><h2>The game</h2><p>Mining station 7. The machines dug too deep, and whatever they woke up has taken over the droids.</p><p>You fight through three levels: HANGAR 7, PROCESSING PLANT and THE CORE. Find the keycards, ride the lifts, avoid the acid and the lava, find the secrets and take down the Warden that guards the core.</p></section><section><h2>Screenshots</h2><div class="grid"><figure><img src="../images/hall.png" width="960" height="600" loading="lazy" alt="IRON ABYSS – HANGAR 7"><figcaption>HANGAR 7</figcaption></figure><figure><img src="../images/courtyard.png" width="960" height="600" loading="lazy" alt="IRON ABYSS – HANGAR 7"><figcaption>HANGAR 7</figcaption></figure><figure><img src="../images/fight.png" width="960" height="600" loading="lazy" alt="IRON ABYSS – HANGAR 7"><figcaption>HANGAR 7</figcaption></figure><figure><img src="../images/plant.png" width="960" height="600" loading="lazy" alt="IRON ABYSS – PROCESSING PLANT"><figcaption>PROCESSING PLANT</figcaption></figure><figure><img src="../images/yard.png" width="960" height="600" loading="lazy" alt="IRON ABYSS – PROCESSING PLANT"><figcaption>PROCESSING PLANT</figcaption></figure><figure><img src="../images/cavern.png" width="960" height="600" loading="lazy" alt="IRON ABYSS – THE CORE"><figcaption>THE CORE</figcaption></figure><figure><img src="../images/warden.png" width="960" height="600" loading="lazy" alt="IRON ABYSS – THE CORE"><figcaption>THE CORE</figcaption></figure></div></section><section><h2>The engine</h2><p>The engine is a PHP port of the software renderer and game logic of the 1993 engine, whose C source was released under the GNU GPL. It has the BSP walk, walls drawn column by column, floors and ceilings as visplanes, colormap lighting, 8-angle sprites, 35 tics a second and the monster AI.</p><p>The same PHP code runs on the desktop and in the browser, compiled to WebAssembly with JumPHP. Every frame, PHP computes a 320 × 168 picture, then WebGL puts it on the screen.</p><p>All the content is original and made by code: the textures, the sky, the monsters (modelled in 3D, then photographed from 8 angles), the weapons and the sounds.</p></section><section class="cols"><div><h2>Monsters and weapons</h2><ul class="list"><li><strong>Husk</strong>: a hijacked drilling droid that fires bursts.</li><li><strong>Gnasher</strong>: a fast beast that bites up close.</li><li><strong>Spitter</strong>: claws up close, acid balls from afar.</li><li><strong>Warden</strong>: the armoured guardian of the core, with a plasma cannon.</li></ul><p>Wrench, sidearm, scattergun, riveter and ion launcher.</p></div><div><h2>Levels</h2><ul class="list"><li><strong>HANGAR 7</strong>: hangar, open-air courtyard, computer room, red keycard.</li><li><strong>PROCESSING PLANT</strong>: acid channels, storage, a yard with stairs, blue and yellow keycards.</li><li><strong>THE CORE</strong>: lava cavern, antechamber, the Warden's arena.</li></ul></div></section><section><h2>Controls</h2><table><tr><td>Arrows / W S</td><td>move, turn</td></tr><tr><td>A D</td><td>strafe</td></tr><tr><td>Shift</td><td>run</td></tr><tr><td>Ctrl / F / click</td><td>fire</td></tr><tr><td>Space / E</td><td>open, use</td></tr><tr><td>1 to 5</td><td>weapons</td></tr><tr><td>Tab</td><td>map</td></tr><tr><td>Escape</td><td>menu</td></tr><tr><td>Gamepad</td><td>stick, RT fire, A use</td></tr><tr><td>Phone</td><td>touch stick and FIRE / USE buttons</td></tr></table><p style="text-align:center;margin-top:24px"><a class="play" href="../play/">▶ PLAY NOW</a></p></section><section><h2>Questions</h2><dl><dt>Is it free?</dt><dd>Yes. It runs in your browser, with nothing to install and no account.</dd><dt>Is it the 1993 game?</dt><dd>No. Only the engine is a PHP port of the source code released under the GPL. The name, the monsters, the weapons, the levels, the graphics and the sounds are original, and no file of the original game is used.</dd><dt>Why PHP?</dt><dd>To show that a language people think of as a web language can run a real software 3D engine, at 60 frames a second in the browser.</dd><dt>Where is the code?</dt><dd>The code is free software, under the GNU GPL v2. You can browse the sources on the project page.</dd></dl></section><section><h2>Credits</h2><p>Engine ported to PHP from the source code of the 1993 engine released by id Software under the GNU GPL. JumPHP framework. Original content.</p></section></main><footer>IRON ABYSS · GNU GPL v2 · <a href="../">Français</a> · <a href="./">English</a></footer></body></html>