It’s the birthday week of one of gaming’s most influential first-person shooters: Half-Life.

Without Half-Life, we wouldn’t be blessed with not just future FPSs featuring gripping and immersive single-player campaigns (or at least attempt to), as well as developers creative enough to make mods out of its engine, leading to competitive genre game-changers like Team Fortress and Counter-Strike. So to celebrate the game’s 25th anniversary, developer/Steam owners Valve made the game free until 21st November 2:00am GMT+8.

The game also comes with a number of new updates:

• Half-Life Uplink – Originally released as a CD exclusive for magazines and hardware manufacturers, this mini-campaign was built by the Half-Life team right after the game went gold.
• Four New Multiplayer Maps – Built by Valve level designers, these new maps push the limits of what’s possible in the Half-Life engine.
• Updated Graphics Settings – Play the game the way it looked in 1998, but on a modern monitor.
• UI Scaling Support for Higher Resolutions – We built most of this stuff for 640×480 CRTs and apparently some of you have upgraded since then.
• Controller and Steam Networking Support
• Steam Deck Support!

The update also comes with a one-hour documentary on the making of Half-Life, made in partnership with Secret Tape, an offshoot of video content creators Noclip.

As to whether this will lead to Half-Life 3? Probably not, but it is a nice celebration of the 1997 game that influenced many game developers and inspired a lot more folks to pursue gaming as a career. Full patch notes below:

New Content

• Now Verified on the Steam Deck (and our native Linux runtime has been set as the default).
• Half-Life: Uplink — the original standalone Half-Life demo — has been added to the game, and is accessible through the “New Game” menu.
• Added four all-new Half-Life Deathmatch maps: contamination, pool_party, disposal, and rocket_frenzy
• Added three old Half-Life Deathmatch maps formerly available only on the “Half-Life: Further Data” CD: doublecross, rust_mill, xen_dm.
• Added Ivan the Space Biker, Prototype Barney, Skeleton, and Too Much Coffee Man as player models to Half-Life Deathmatch.
• Added dozens of new sprays formerly available only on the “Half-Life: Further Data” CD.
• Added support for Steam Networking, allowing easy multiplayer via Steam’s Join Game and Invite features.
• Added support for Steam Friends Rich Presence, allowing your friends to follow your journey through Black Mesa.

Nostalgia

• Brought back the original Valve Intro video. Can be skipped with the “-novid” launch command.
• Updated main menu to a design inspired by the game’s original 1998 main menu.
• Changed the default models to the original (non “HD”) models.

Gameplay Changes

• Improved physics for throwing grenades.
• Improved randomness for initial spawn points in multiplayer.
• Improved satchel charge controls: primary fire now always throws a new satchel, and secondary fire always detonates.
• Fixed push-able entity movement being based on framerate.
• Fixed players with high framerates freezing in place on death in multiplayer.
• Fixed some cases where the player could get stuck in place on level transitions.
• Fixed some cases where characters would interrupt important dialogue with their “greetings” dialogue.
• Fixed weapon view-bob angles.
• Fixed red barrels at the start of Surface Tension not launching as intended.
• Fixed Snarks attacking FL_WORLDBRUSH entities (such as func_walls).
• Fixed players sometimes failing to deploy a snark while crouching and looking down.
• Fixed certain convars (“pausable” and “sv_maxspeed”) being set to incorrect values when entering a singleplayer game after a multiplayer game.
• Fixed singleplayer auto-aim setting being changed when entering a multiplayer game that disallows auto-aim.
• Fixed the flashlight HUD showing empty after loading a savegame.
• Fixed rockets in CONTENTS_SKY not always detonating.
• Fixed incorrect bullet impact sounds for NPCs.
• Fixed gauss gun making a loud static noise if it was charged across level transitions.
• Fixed a crash in mods that display keybinds in their UI.
• Fixed singleplayer weapons not auto-switching away when exhausted (grenades / snarks / satchels / etc)
• Fixed interpolation artifacts when animated models are moved by other entities.
• Fixed some buffer overflow exploits.

UI Changes

• Main-menu background and buttons have been reskinned, and now scale based upon screen resolution without stretching, supporting background image layouts up to 3840×1600.
• In-Game HUD now uses double or triple sized sprites when playing at higher resolutions.
• UI dialogs and in-game fonts now scale to improve readability at high screen resolutions.
• In-Game HUD HEV suit display has been shifted to the left of the screen, and no longer changes position at larger screen resolutions.
• Added an “Enable texture filtering” setting.
• Added an “Allow widescreen Field of View” setting to correct non-anamorphic FOVs, for widescreen and ultrawide displays.
• Re-organized all the Settings screens to improve legibility, and support controller navigation.
• Updated the Pause menu to be aware of the current gameplay mode.
• The default server name and multiplayer player name are now based on the player’s Steam Persona.
• The Steam platform menu has been removed, now that all its features are in Steam itself.
• Fixed application icon rendering incorrectly when using the software renderer.
• Fixed player and spray images not updating their coloring on the settings screen.
• Removed the now very unnecessary “Low video quality. Helps with slower video cards.” setting.

Input Changes

• Improved support for keyboard and controller navigation everywhere.
• Added “Lower Input Latency” option: Synchronizes the CPU and GPU to reduce the time between input and display output.
• Fixed issues that caused jerky mouse / joystick input.
• (We basically rewrote it all – if you’ve got a custom Steam Input controller configuration, you should rebuild it from our newly published Official Configuration).

Multiplayer Balancing

• Increased the 357 damage from 40 ? 50.
• Hive Hand reload time has been reduced from 0.5s ? 0.3s per shot, and it will be selected at higher priority than the pistol on pickup.
• MP5 now always starts with full ammo when initially picked up.
• Players no longer drop empty weapons, and any that are dropped are reloaded by what’s in the dying player’s backpack.
• Improved client-side prediction to reduce “ghost shots”. Like Counter-Strike, consider hitboxes and not just bounding boxes for hits on the client.
• Fixed network predicted crowbar swing damage being incorrect.

Rendering

• Added setting to turn off texture filtering when using the OpenGL renderer.
• Default gamma has been decreased from 2.5 ? 2.2, now that we aren’t all playing on CRTs.
• Restored OpenGL overbright support.
• Added support for UI Sprites and Texture files larger than 256×256.
• Added support for UI Font special render modes: “blur” and “additive”.
• Default resolution is now based on the resolution of the desktop, instead of a 640×480 window.
• Software renderer will now correctly filter out incompatible resolutions, unless there is only 1 resolution available on the display.
• Fixed fullscreen software renderer crashing on systems that don’t support 16-bit color.
• Fixed software renderer being stretched when using widescreen resolutions.
• Fixed skyboxes and sky color incorrectly carrying over when transitioning maps in multiplayer.
• Fixed the game appearing too dark after modifying video settings.
• Fixed MSAA in windowed mode.
• Fixed mipmap rendering on studio models.
• Fixed gluon gun sprite rendering in multiplayer.
• Fixed gluon gun sinusoidal noise being incorrect.
• Various optimizations to support the newly increased engine limits.
• OpenGL optimizations for the Steam Deck.

Engine Improvements for Mod Makers

• Increased maximum limit of dynamic sound channels from 8 ? 32.
• Increased maximum limit of sentences in the sentences.txt file from 1536 ? 2048.
• Increased maximum number of entities (MAX_EDICTS) from 900 ? 1200.
• Increased MAX_PACKET_ENTITIES from 256 ? 1024.
• Increased MAX_GLTEXTURES from 4800 ? 10000.
• Increased software renderer geometry limits: max spans 3000 ? 6000, max surfaces 2000 ? 4000, and max edges 7200 ? 14400.
• Cycler and func_button entities can now be the entity target for scripted_sentence entities, and are allowed to speak in multiplayer.
• Incorporated func_vehicle entity support from Counter-Strike, for mod-makers to use. Full SDK update will come later, but level designers can use it now.

Native Linux Build

• Added support for the software renderer.
• Improved font rendering.
• Many stability and behavior fixes.

Other

• Localization files updated.
• Miscellaneous security fixes.

Notes

• The previous version of the game has been archived to a publicly visible Beta branch named “steam_legacy”, with the description “Pre-25th Anniversary Build.” If a mod or feature is behaving in an unexpected way, you may need to run this archived build until the issue is resolved in the default build.
• We now consider this anniversary version of Half Life to be the definitive version, and the one we’ll continue to support going forward. Therefore, we’ll be reducing the visibility of Half Life: Source on the Steam Store. We know Half-Life: Source’s assets are still being used by the Source engine community, so it’ll remain available, but we’ll be encouraging new Half-Life players to play this version instead.