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 $84.5K — a different platform, not this one.

GUNHEAD

Gunhead is a FPS roguelite that challenges players with boarding and neutralizing procedurally generated alien starships to earn income for their Privateering enterprise. The decaying alien arks will defend themselves from intruders with a wide arsenal of cyborg monstrosities, robotics, and security systems, all obstacles that must be surpassed to achieve victory: the destruction of the ship’s central System Core. Gunhead is a sequel to Alientrap's previous game Cryptark - taking its strategic fast paced 2d gameplay and expanding it to an roguelike FPS experience. Complex, procedurally generated alien space-hulks to board and defeat. Fast paced jetpack-enabled FPS gameplay with 4 gun slots ready to be configured with over 50 weapon options Each enemy ship is its own unique challenge. Set your loadout strategize a plan of attack to take out the complex interconnected enemy security systems. Blood-pumping soundtrack perfect for intense firefights.