Metal Slader Glory is an adventure game developed and published by HAL Laboratory for the Family Computer in 1991.

Earth-based mechanic Tadashi and his girlfriend discover a mech from a war eight years past with an ominous message stored in its memory suggesting Earth is in danger.

Tadashi decides to venture to nearby space colonies along with Elina and his younger sister Azusa to investigate the origins of the mech.

As the company drove towards bankruptcy, they ceased independently publishing console games and entered a close affiliation with Nintendo.

Tadashi, Elina and his younger sister Azusa decide to fly to the nearby space stations and colonies near Earth and the Moon to investigate the mech's origins and the meaning of the strange message.

As they continue to search for who may have designed or built Glory, a shape-shifting alien infiltrates their ship and kidnaps Azusa.

In their search for Azusa and solving the mysteries of Glory, they discover a secret organization of Slader pilots that had worked with Tadashi's father.

Because the aliens have the ability to take on the appearance of humans and infiltrate society, the Slader pilots prefer to stay a secret organization away from the potentially compromised government.

Tadashi pilots Glory in a battle with the aliens and is ultimately successful at destroying their ship and saving Earth.

Development of Metal Slader Glory was led by artist Yoshimiru Hoshi (typically referred to by his first name).

[5] Students and freelancers were proposing projects to HAL at this time,[5] so Yoshimiru began working on an original game based upon his cancelled Fixallia manga.

Yoshimiru believes the graphics, particularly the large animated characters, looked more advanced than any other Famicom artwork at the time and this is what won over Iwata.

[5][7] Yoshimiru lead the project, writing the script, planning the gameplay, creating sound effects, and drawing the artwork and animations.

[7] Once a team was built, Yoshimiru spent the first six months working with programmers to help them understand the type of game he wanted to build.

The hardware was capable of holding 128x128 pixels worth of data in "banks" which held the tiles to be displayed on screen at any one time.

[5] Working with the tiles to create impressive imagery and save space was the main reason for the game's protracted development.

[5] Yoshimiru created his artwork with home television sets in mind versus the professional video monitors used in the office.

[5][7] Development of Metal Slader Glory lasted a long four years,[6] and with one megabyte of data,[10] was the largest game for the Famicom.

Also, when Nintendo revealed the system architecture for their next home console, the Super Famicom, the team believed they could potentially transfer their progress to the new platform.

[5] When it became clear there was not enough space to fit the opening Yoshimiru wanted into the game, he spoke to HAL's public relations representative and got approval to include it as a manga in the manual.

Nintendo sold a limited number of boards to HAL at a discount so they could afford to sell Metal Slader Glory at a competitive market price[6] of 8900 yen.

[7] The long development cycle, expensive cartridges, and lack of sales brought on financial strain to HAL Laboratory.

[6] Beyond Metal Slader Glory, the company's growing success through the late 1980s pressured programmers to release games faster and place less effort on quality.

[12] Although this release delighted Yoshimiru, as it gave more people an opportunity to play it, he was disappointed they would not be familiar with the backstory, which had been included with the original game manual.

[15] It was the last officially released game for the system,[16] and was distributed exclusively for Nintendo Power flash cartridges.

[18] This version features improved graphics and additional story sequences cut from the original game due to size constraints.

[6] Since his artistic style had changed over time, he created the new artwork based on the originals, adding colors, highlights, and shadows.

[6] Famitsu commended the cinematic-style visuals, but faulted the linear plot and lack of an option to speed up in-game text.

[27] A writer at Japanese gaming magazine Yuge commended the high quality visuals, futuristic scenario and command-based gameplay system.

[28] ITmedia praised the game's visuals, character design, and animation, but complained about getting lost exploring some areas.