Vulkan became an optional graphics API for Dota 2 in May 2016.
Valve introduced Vulkan support through a beta update on May 24, 2016, allowing players to select it instead of the game’s existing OpenGL renderer. Vulkan was designed as a lower-overhead, cross-platform API that could give modern GPUs more direct access to graphics hardware.
The addition was notable because Dota 2 was among the earliest major games to support Vulkan, which was developed by the Khronos Group as an open alternative to proprietary graphics APIs. Players generally enabled the feature through a separate Steam DLC package and a launch option during its early rollout.
Vulkan is not the same thing as DirectX 12, although both target similar low-level rendering advantages. OpenGL remained another rendering option, while Metal is Apple’s graphics API and was not the answer to this Dota 2 update question.