Both games run on the Source engine. This means HL2 assets do not just look right; they behave perfectly. The ragdoll physics of a Combine Soldier or the weight of a rusted car chassis respond flawlessly to GMod's Tool Gun and Physics Gun. A Masterclass Asset Library
For years, accessing certain assets in GMod required players to own other Source Engine games like Counter-Strike: Source and the Half-Life 2 episodes. A landmark update in July 2025 changed everything, integrating most assets from these titles directly into GMod. Now, players no longer need to install separate games to spawn a Combine Elite or build a scene with Episode Two assets, removing a major barrier for creators and ensuring wider access to the complete Half-Life 2 toolkit.
So, what will you create in the ruins of City 17? The only limit is your imagination.
If you don't own the original games, you might be tempted to download "Content Packs" from third-party websites.
HL2 introduced advanced skeletal animation and facial flexing. In GMod, this spawned an entire sub-culture of digital puppetry. Players use the "Physics Gun" and "Tool Gun" to pose Gordon Freeman, G-Man, or Alyx Vance for screenshots, comic strips, and machinima. 3. Weapons and Entities
As of the , Garry’s Mod now includes most content from Counter-Strike: Source and Half-Life 2: Episodes 1 & 2 by default. However, for full access to maps, music, and the original campaign experience, manual mounting and specific workshop addons remain critical. 1. How to Mount Half-Life 2 Content