Golvellius is an action adventure video game for the Japanese MSX home computer system. It was developed by Compile and released in 1987.
Sega licensed the franchise in 1988 and released their own remake of the game for the Sega Master System (the Mark III in Japan), featuring enhanced graphics and entirely different overworld and dungeon layouts. This game got released worldwide under the name Golvellius: Valley of Doom.
Later that year (1988), Compile released yet another remake of Golvellius for the MSX2 system. This game featured mostly the same graphics as the ones in the Sega Master System version, but the overworld and dungeon layouts are entirely different.
In 2009 it was announced by DotEmu/D4 Entreprise that Golvellius was to be re-released for the iPhone OS platform.
The scenario is the same in all the three different versions of Golvellius. The ending promised a sequel, which was never developed/released.
Source: Wikipedia, "Golvellius", available under the CC-BY-SA License.