GoldSrc (25th anniversary)
- Steam Input support - Steam Input support was added to the game with the Half-Life's 25th Anniversary update, which allows the game to support more controllers and buttons.
- Rudimentary Shadows

- 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.
- Increased engine limits - Valve has increased engine limitations with the Half-Life's 25th Anniversary update, allowing for more entities and detailed maps.
|- ! GoldSource Limits !! Pre-25th !! Post-25th |- | Maximum number of dynamic sound channels || 8 || 32 |- | Maximum number of server entities (MAX_EDICTS) || 900 || 1200 |- | Maximum number of temporary entities (MAX_TEMPENTS) || 500 || Unchanged[confirm] |- | Maximum number of particles (MAX_PARTICLES) || 4096 || Unchanged[confirm] |- | Maximum number of beams (MAX_BEAMS) || 64 || Unchanged[confirm] |- | Maximum number of visible entities in the package (MAX_VISIBLE_PACKET) || 256 || 1024 |- | Maximum number of pre-cacheable models/sprites (MAX_MODELS) || 512 || Unchanged[confirm] |- | Maximum number of pre-cached sounds (MAX_SOUNDS) || 512 || Unchanged[confirm] |- | Maximum number of entries to read sentences made up of sentences (MAX_SENTENCES) || 1536 || 2048 |- | Maximum number of user messages (MAX_USER_MESSAGES) || 128 || Unchanged[confirm] |- | Max number of loaded textures (MAX_TEXTURES) || 2048 || Unchanged[confirm] |- | Max number of GL textures (MAX_GLTEXTURES) || 4800 || 10000 |- | Number of messages titles.txt (MAX_MESSAGES) || 1024 || Unchanged[confirm] |- | Maximum size of indexed textures || 512х512 || Unknown |- | Maximum size of full color textures || - || - |- | Maximum number of models on the map (MAX_MAP_MODELS) || 256 || Unchanged[confirm] |- | Maximum number of map leafs (MAX_MAP_LEAFS) || 8192 || Unchanged[confirm] |- | Maximum number of entities per packet (MAX_PACKET_ENTITIES) || 256 || 1024 |- | Maximum number of spans (software renderer geometry limit) || 3000 || 6000 |- | Maximum number of surfaces (software renderer geometry limit) || 2000 || 4000 |- | Maximum number of edges (software renderer geometry limit) || 7200 || 14400 |}