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 $21.4K — a different platform, not this one.
Flame Keeper
Become Ignis, a special coal tasked with liberating that world of Orbis, recently overrun by forces of darkness. Luckily, it just so happens that you're trained in the art of mortal combat! Learn how to fight, upgrade your abilities, venture through increasingly hostile worlds, and restore the Eternal Flame. FIGHT, ADAPT, AND PERSEVERE Adapt and take on enemies using a multitude of moves and attacks including punch combos, fiery dashes, wide area-of-effect stomps, and powerful finishers that deal decisive damage. But don't get too reckless - smart stamina usage is essential. Each biome in Flame Keeper is inhabited by unique foes and obstacles of increasing difficulty. Consult the trusty Bestiary as you unlock insight into the strengths and weaknesses of your enemies. YOUR IGNIS, YOUR PLAY STYLE It's not enough to let your fists do the talking. Sometimes... you need a little pick-me-up. Upgrade Ignis to your heart's desire via skills and passive abilities. Collect seeds from defeated enemies to learn new skills and complete specific tasks to receive runes and unlock helpful passive abilities. Mix and match to create tons of different builds! HERE'S TO YOUR HEALTH To restore the Eternal Flame, you must scour each environment for what remains of its energy and transfer it back into each stage's Fire Camp. Here's the twist: the energy you collect also acts as your health. You need to deplete it to charge up each Fire Camp, but you also have to stay healthy to explore ever deeper. Find the right balance and discover your best way to play. RECHARGE IN VULPIS VILLAGE At the start of each level lies Vulpis Village. The Vulpis are friends to a brave charcoal like yourself, so they're happy to provide a service. Here you can rest, enhance abilities, rebuild and upgrade structures thanks to the resources you collect. The village changes along with your progress and opens up all-new gameplay features each time.