Getsufuu Maden (also known as Guardian Legend) is an action game released in 1989 for the Nintendo NES. The game uniquely blends top-down shooting segments with exploration-based adventure gameplay. Players control a transforming protagonist who can switch between a humanoid form and a spaceship, navigating through labyrinthine corridors and engaging in intense shooting battles.

The main objective is to infiltrate and destroy a massive alien spaceship to prevent it from threatening Earth. The game's pace varies between fast-paced shooting stages and slower, methodical exploration phases where players collect items, solve puzzles, and upgrade their abilities. This dual-genre approach offers a distinctive rhythm uncommon in NES titles.

A notable mechanic of Getsufuu Maden is the ability to shift between two gameplay styles seamlessly, combining vertical scrolling shooter sequences with overhead adventure exploration. The game’s unusual idea of merging these genres results in a multifaceted experience, setting it apart from typical action games of its era.