A sidescrolling speedrun game with Quake III Arena movement, in your browser.

No enemies. No shooting at anything that shoots back. Just you, a course, and a clock. The weapons are there to move you: rockets to launch off, plasma to climb with, grenades to ride. Everything Q3 players have been drilling since 1999 works here, because the movement code is a line-by-line port of Quake III's, bugs included.

This project is pure slop. It is entirely AI generated, and no meatbag has touched any of the code.

The load-bearing counter: 71

Nothing to install, nothing to sign into. Ten courses are built in. Bring your own Quake III or OpenArena maps if you want more.

Everything you have ever done is on that screen: attempts, distance, top speed, deaths.

Light shafts, coloured liquid, real shadows. Quake's maps with a modern renderer on top.

WebGPU, with AgX tone mapping, ambient occlusion, shadow maps, volumetric fog, lava that blooms and shimmers, and motion blur.

Water you can see into, and see reflected off.

Prefer it the old way? Faithful 1999 is one click and turns every bit of that off, down to Quake's own blob shadow. Or set each effect yourself. None of it can change how the game plays: the physics cannot see the renderer.

Three cameras, and the side one is the point.

• Side is what the game is built around. The world is fully 3D, you just watch it from the side, so you can see the gap you are about to clear and the pad you are about to overshoot. Some courses lock the camera to a rail and follow a script the mapper wrote.
• Chase sits behind you.
• First person draws the gun in your hands, with Quake's own walk bob and landing dip.

Pick per course. Your choice is remembered for that map.

Three things to learn.

Strafe jumping. Hold a strafe key, turn that way, and keep jumping. Quake only measures your speed along the direction you are asking to go, so the 320ups cap never catches you. Good runs pass 1200ups inside ten seconds.

Rocket jumping. Fire down and jump at the same moment. Firing alone is not enough.

The overbounce. Land in the eighth of a unit where Quake skips its collision clipping and you keep all of your falling speed. Arrive with speed and it flings you sideways. Arrive with none and it fires you straight back up as fast as you came down, which is how you reach places you otherwise cannot. The spots are exact coordinates on exact maps, so the HUD tells you when one is under you and how you would have to hit it.

Seven are built for the game: ob_basics teaches movement, ob_rockets is rocket and grenade jumps, ob_crypt runs over lava through jump pads and a vertical overbounce down an iron shaft, ob_yard is floating slabs in a starfield where some pads only reach the next platform if you strafe mid-flight, ob_grounds is a gothic courtyard of ground strafe jumps with no ceiling in the way, a fog garden, and a last gap you make by turning a fall into speed, ob_strafes is a temple over the void: eight ever-wider strafe jumps between floating islands you chain at speed, a gap built for a quad rocket jump, and two quad rockets out of a deep pit, and ob_circuit is a descending sci-fi circuit of three crossings, each with a high, a middle and a low line to choose from (jump pads, strafe jumps, rocket jumps, overbounces and a slick slide), so there are 27 ways through it.

Three real DeFRaG maps ship too: de4th_run1, de4th_run2 and acc_fuzzle.

Past that, bring your own. Drop a .pk3 on the course list and it shows up next to the built-in ones. Quake III and OpenArena maps work properly, not approximately: triggers, jump pads, teleporters, doors and buttons all behave the way the mapper intended. Maps built for DeFRaG time themselves correctly.

CTF maps time themselves too. A ctf map has no start gate, so the flags are the gates: grab either flag, reach the other team's, and that is your run. Both directions count and share one record. These show up as CTF on the course list rather than FREERUN — q3ctf1 and q3ctf2 are two of the best maps in the game and now there is something to beat on them.

You do not need it. What ships here is OpenArena, which is free, and the game is complete with it.

You need it for q3dm6, q3dm17, q3ctf1 and the rest — the maps in the screenshots above, with the textures and the sounds id shipped. Those files are not free and are not in this repository, and never will be. You buy the game, you point Overbounce at pak0.pk3 from your own baseq3 folder, and it loads.

• Steam — the usual place. It will probably not sell it to you in the EU: Quake III Arena is on the German index, and the store honours that across the region.
• k4g — a global Steam key, which is how EU players get around the above. It activates the same Steam copy.
• GOG — usually the cheapest, and the only one on this list that is not a Steam key: you get a plain installer, so the paks are yours as files without Steam in the middle. Often the least painful route to pak0.pk3.
• Fanatical, Green Man Gaming, Humble — all Steam keys, and worth a look when one of them is discounting.
• An old disc. The 1999 CD works, and so does the Quake III Gold / Team Arena box. Any baseq3/pak0.pk3 is the file.

Overbounce reads the pak in your browser. Nothing is uploaded, and nothing leaves your machine.

Every finish is timed and kept. Afterwards you get your splits against your best, segment by segment, your top and average speed, how long you spent in the air, how much of the available strafe gain you actually took, and the whole run drawn as one speed trace with your jumps and shots marked on it.

Ghosts race you properly. A ghost is a recording of the keys you pressed, replayed through the same physics, so it goes exactly where you went. Export one to send to a friend: a run of about fifteen seconds packs down small enough to paste straight into a Discord message, and longer ones save as a file.

Records are kept per course and per mode. The same map in VQ3 and in CPM, or from the side camera and first person, keeps separate personal bests.

Anything that makes it easier stops the clock: pausing, dying, or turning off self-damage.

Watch your own runs back, or watch Quake III .dm_68 demo files. Drop a demo in and it plays, including demos recorded in Quake III itself two decades ago. Your own personal bests show up in the library automatically.

Hit T for the timeline and the camera becomes yours:

• Fly it anywhere on your normal movement keys, then double-click a track to drop a keyframe. The camera flies between your keyframes on whichever easing curve you pick.
• Keyframe the camera position, FOV, vignette and chromatic aberration.
• Cut between free, first person, chase and side mid-shot.
• Set in and out markers to trim.
• Export video writes a real WebM file frame by frame, not a screen recording, so a slow machine gives you the same video as a fast one. Sound included.

Pause anywhere and fly the camera. Move speed, field of view, roll, exposure, tone mapping, vignette, chromatic aberration. Hide the player model or the gun. Then take the screenshot.

All rebindable in Settings, two binds per action.

The weapon keys are Quake III's own numbers, gaps and all — 1, 6 and 9 are the gauntlet, the lightning gun and the BFG, none of which exist here. Pick up a weapon you were not already carrying and it is equipped for you; that is a switch in Settings if you would rather it was not.

Right-click jumps because rocket jumping needs fire and jump on the same hand, within a frame of each other.

VQ3 is the default and matches Quake III exactly.

CPM gives you air control, ramp jumps and the 400ms double-jump window. It is reconstructed from CPMA's own shipped game files rather than ported, because CPMA is closed source. On slick floors it accelerates like DeFRaG's promode, so speedbelts such as flow's work.

• Every URL parameter
• Developing Overbounce

GPLv2-or-later. The movement and collision code derives from id Software's GPLv2 Quake III Arena source. See LICENSE and NOTICE.

The three bundled DeFRaG courses are GPLv3. NOTICE explains what that means for redistribution and what to drop for a v2-only build.

Assets come from OpenArena. Assets from a commercial Quake III Arena installation are not redistributable and must never be committed here.

Overbounce is not affiliated with or endorsed by id Software or Bethesda Softworks.