No revenue estimate for GOG — its rating/review counts don't calibrate to sales the way Steam's do. The Steam version is estimated at $72.7K — a different platform, not this one.

Splatter - Zombiecalypse Now

Splatter is a top-down-shooter with a film-noir-singleplayer-campaign. Fight against all kinds of monsters hordes with a huge arsenal of weapons, all with top of the line physics-based splatter effects and destructible level environments. Meet interesting characters, accomplish dozens of side quests, engage boss fights and upgrade your weapons. The zombies fear light, so use your flashlight strategically to create breathing space in battles and to expose hidden weaknesses of your enemies. Explore the surroundings to find new weapons, resources and secret areas. Spend the money you collect to upgrade your guns and unlock new weapon features and discover the best tactics against the variety of monsters. The story mode spans 16 levels with fully voiced NPCs and dialogs and animated cutscenes. Try to beat the Highscores in the Survival Mode or gather up to 4 friends in front of your computer to co-op against the horde. Key Features Topdown shooter with challenging fights against all kinds of zombies and monsters Film-noire-singleplayer-campaign with fully voiced dialogs, cutscenes, bosses, vehicles and side missions Lights and Shadows add a tactical layer to the battles A destructible environment to shatter, with occasional resources hidden inside Upgradeable weapons gain new qualities and features with each level Arcade game modes with online leaderboards pit you against your friends' scores Local multiplayer for upto 4 players with controllers, mice, keyboards... whatever you got there, you can use it And lots of action, of course