HEXAeco is an energy company known to have facilities in Grand Metropolis, which were briefly seized by Metal Sonic while he was impersonating Dr. Eggman as head of the Eggman Empire. Team Sonic, Team Dark, Team Chaotix, and Team Rose all passed through HEXAeco facilities during their efforts to stop the villainous robot. Later, during the Shattered World Crisis, HEXAeco would step up as a sponsor for Breezie the Hedgehog's Chaos Emerald Championship, along with the Meropis Tourism Board and MeteorTech. (VG: SH, StH: #269)
HEXAeco first appeared in the game Sonic Heroes as the setting for the Grand Metropolis and Power Plant levels.