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 $8.5M — a different platform, not this one.

Hyper Light Drifter

Explore a beautiful, vast and ruined world riddled with dangers and lost technologies. Echoes of a dark and violent past resonate throughout a savage land, steeped in treasure and blood. Hyper Light Drifter is an action adventure RPG in the vein of the best 16­bit classics, with modernized mechanics and designs on a much grander scale. Drifters of this world are the collectors of forgotten knowledge, lost technologies and broken histories. Our Drifter is haunted by an insatiable illness, traveling further into the lands of Buried Time, hoping to discover a way to quiet the vicious disease. From each character to subtle background elements, everything is lovingly hand-animated. Easy to pick up, difficult to master; enemies are vicious and numerous, hazards will easily crush your frail body, and friendly faces remain rare. Upgrade weapons, learn new skills, discover equipment and traverse a dark, detailed world with branching paths and secrets abound.