"Knightmare" has a knight shooting his way up a monster-infested tower, with power-ups that upgrade the weapon and speed, in a vertical action formula closer to a shooter than a pure platformer. Konami also released it for the Famicom, but it's on the MSX where the saga found its most memorable continuation with "Maze of Galious," one of two sequels that expanded the universe toward non-linear exploration.
It's the starting point of a trilogy now cited as an early forerunner of the "metroidvania" format, especially because of what came later in its MSX sequels.
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