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 $4.9M — a different platform, not this one.
Gauntlet™ Slayer Edition
Also onSteam
The classic Gauntlet 4-player co-op action gameplay returns in a completely new experience! Play as one of four distinct heroes in an intense monster filled dungeon brawler with a combination of both uniquely built and randomly generated levels to explore. Battle the endless hordes of foes as you and your friends fight for treasure and glory via both local and online co-op multiplayer. Invade the Darkness! New Gauntlet Experience Classic dungeon crawling action is melded with innovative new features for the ultimate Gauntlet challenge. Online and Couch Co-op Multiplayer Explore on your own if you dare or play with friends in 4-player same-screen and online co-op. Your friends can become foes as you compete to see who can claim the most kills and the most gold. Four Classic Characters Gauntlet’s four classic characters: Warrior, Valkyrie, Elf, and Wizard return but with more distinctive play styles and their own unique skills. Discover New Powers Players can scour the dungeons for gold and loot to unlock mystical Relics that grant the holder deadly new abilities. But beware – if used incorrectly they can be detrimental to your party’s health! How Will You Die? Fiendish traps, monstrous hordes, epic bosses and even your own friends will cause you to die in confounding and extraordinary ways. Accolades: An idealized reboot of the series – immediately familiar yet totally fresh. – Digital Trends You haven’t needed food this badly since the 1980’s – Gamespot Just the way fans would want it - Destructoid Fans of the classic 80s game have nothing to worry about. - PrimaGames This classic quarter-muncher consumed a lot of my own money during summers as a kid, so it's nice to see the fantasy gameplay live on this latest incarnation. - Fortune With its simple, streamlined controls and the compatibility with SteamOS, 'Gauntlet' is clearly nostalgic for the living room-centric gaming of the early 90s. And it succeeds. - Tom's Guide