The gameplay focuses on darkness as a key mechanic, where Garcia's health starts to drain if he stays in bright areas for too long. To avoid this, players must use special light bullets to illuminate their surroundings, shoot goat heads, set off fireworks, or kill demons that spread the darkness. Interacting with non-playable characters, such as Colonel and Christopher, also plays a role in the gameplay.
Some levels feature unique gameplay mechanics, such as 2D side-scrolling shooter segments with distinct art designs. The game's tone is often humorous, with over-the-top action and engaging conversations.