The official release build of Rat Dungeon! Install instructions packaged with the game and on this page.
Install Instructions:
1. Navigate to your Steam library. In the top-left corner, there will be a search bar. Search for Source SDK.
2. Under the 'Tools' category, you will find a list of various Source SDK tools. 'Source SDK Base 2013 Multiplayer' is the one required. Install it.
3. While Source SDK installs, navigate to your steam install directory on your system (usually <main drive>\Program Files (x86)\Steam\steamapps).
4. Under 'steamapps,' locate the 'sourcemods' folder.
5. Unzip the 'rat_dungeon' folder from this install. Drag it into the 'sourcemods' folder.
6. Restart Steam once Source SDK has finished installing for the game to appear in your library. It should appear as Rat Dungeon.
7. The game is now ready to play! Launch it through Steam.