Concept artwork for Final Fantasy by Yoshitaka Amano.
The Guardian (ガーディアン, Gādian?), also known as the GUARD, Glasya Labolas, or Fallen Guardian, is a recurring creature in the Final Fantasy series, first appearing in the original Final Fantasy. It is typically a powerful robotic enemy.
Appearances
Final Fantasy
The Guardian, also known as the GUARD, appears as an enemy encountered in the Mirage Tower and the Flying Fortress. It can inflict Paralysis with its basic attacks.
Final Fantasy III
The Guardian appears a boss encountered in Eureka, and uses primarily physical blows. It guards the Ragnarok.
Final Fantasy IV -Interlude-
The Guardian is a dummied enemy found in the files for Interlude in the Complete Collection release. It is based on its Final Fantasy I appearance.
Final Fantasy V
The Guardian appears as a boss encountered in the Sealed Temple in the Advance and Matrix Software releases. It battles with two Wave Cannon attachments.
Final Fantasy VI
The Guardian appears as a unique boss that can be encountered several times but cannot be killed until the last encounter. As the pinnacle of Magitek machinery, it guards the Imperial Palace in Vector, and later guards the entrance to the city after the Magitek Research Facility is invaded. Kefka brings an escort of Guardians to Thamasa, but dispatches them shortly after arriving. In all of these battles, the Guardian is physically impossible to damage and serves to prevent the player from leaving or entering an area, as it only attacks the party when they attempt to pass it.
The Guardian later appears at the summit of Kefka's Tower as the final boss before the Warring Triad. Here it is finally vulnerable to damage and mimics the battle techniques of previous bosses.
Final Fantasy VII
The Guardian appears as an enemy encountered in the Underwater Reactor.
Final Fantasy XIV
Glasya Labolas (top) and the Guardian (bottom).
Glasya Labolas (不壊のガーディアン, Fue no Gādian?, lit. Guardian the Indestructible) appears as the second boss of 
Syrcus Tower. While named for the Guardian from Final Fantasy III in the Japanese localization, the English localization instead names it after the Guardian's palette swap Glasya Labolas. Additionally, a Guardian (ガーディアン, Gādian?) based its Final Fantasy VI appearance acts as the boss of Sigmascape V3.0.
Final Fantasy XVI
The Fallen Guardian (simply Guardian in Japanese) is a recurring mini-boss found amongst the ruins of the Fallen.
Final Fantasy Adventure
The Guardian appears as an enemy encountered within the Cave of Ruins, Dime Tower, and Temple of Mana. It has a chance of dropping Thundr.
Final Fantasy Crystal Chronicles: Echoes of Time
The Guardian appears as the first boss of the game, encountered in the Forest.
Final Fantasy Dimensions
The Guardian appears as a boss encountered in Rosetta Tower.
Final Fantasy Dimensions II
This section about an enemy in Final Fantasy Dimensions II is empty or needs to be expanded. You can help the Final Fantasy Wiki by expanding it.Dissidia Final Fantasy Opera Omnia
The Guardian from Final Fantasy VI appears as a boss.
Pictlogica Final Fantasy
The Guardian from Final Fantasy VI appears as a boss.
Final Fantasy Record Keeper
The Guardians from Final Fantasy III, V, VI, and VII appear as bosses and enemies.
Final Fantasy Brave Exvius
The Guardian appears a recurring boss encountered in the Mobreeze Airship Factory and the Invincible. It is based on its Final Fantasy VI appearance. The Final Fantasy I Guardian also appears as an enemy during the "Mirage Tower" crossover event.