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 $10.6K — a different platform, not this one.

Realms of Antiquity: The Shattered Crown

Prepare yourself for a journey to a world of fantasy and adventure!  A land fallen into chaos needs stalwart heroes to save it from a sinister and powerful force of evil...  Enter a massive sprawling world of wild forests, frozen plains, misty mountains, scorched deserts, and endless oceans. Explore cities, towns and villages to rest and recover as well as buy equipment. Talk to sages, warriors, peasants and sovereigns to aid you in your quest. Sail the open seas or pilot boats up rivers. Descend into dark dungeons, castle ruins, and mysterious places to find treasure, fight evil, and locate powerful relics.  Do you have what it takes to save the Realms of Antiquity?   This is a retro computer role-playing game, written for the classic TI-99/4a home computer, released in 1981. It runs in full emulation on modern Windows systems as well as the original hardware.  Provided ready-to-play in the Classic99 emulator!   Features: 16-Color bitmap enhanced graphics  Nine character classes  Control up to four characters  2d turn-based tactical combat  Huge multi-disk fantasy world  Over 250 unique powerful items  60 spells, seven schools of magic  Over 200 terrifying monsters  NPC’s with complex dialogue