The Blade of Marmora is a group of Galra resistance fighters that has existed for many centuries.
The Blade of Marmora has a hidden main base, shown in the episode 'The Blade of Marmora', Ulaz's outpost, as well as others. The Blade of Marmora has spies working on the inside of Zarkon's command hierarchy, who work with Voltron to take down the Empire piece by piece.
The Blade of Marmora oppose Zarkon's rule over the universe after discovering that the Emperor had more secretive intentions than to sustain peace across the universe. They are allies to the Voltron Force, and even risk some of their own for the sake of intelligence, per their mantra, "Knowledge or death." (A variation of the Galra Empire's "Victory or Death.")
Members (also referred to as "blades") are put through a strenuous amount of trials in order to determine if they are worthy to join the ultimate fight against the Galra Empire. Keith, who was obsessed with the origins of his blade, underwent the trials with great persistence. It was only when his lion attacked that he chose to relinquish it, which in turn, activated the blade. The only way that a blade can be activated is through an example of true self-discipline and heritage of Galra blood. This also revealed that Keith is descended from a Blade, and is therefore a legacy member of the organization. Specifically, he is the son of a Blade named Krolia, a trusted female spy for the resistance group.
Each agent wields a blade made of a rare metal known as luxite. These blades possess the ability to transform from their dormant state, which is typically a small knife inscribed with the organization's insignia, into a larger sword. The design of both the dormant and awakened states varies from member to member; Keith's bears a resemblance to the Egyptian khopesh. The blades are connected to their owner's life force, and will cease to glow when they are dead.
Following Voltron's victory over Zarkon and the rise of Prince Lotor, Keith formally joined the Blade of Marmora so as to distance himself from Team Voltron to ensure a returned Shiro could pilot the Black Lion. During his time with the Blades, he began tracking a highly pure source of quintessence, which concerned the Blades, as they assumed the destruction of the Komar would halt the Galra Empire's harvest. Eventually teaming with Krolia, they discovered that Lotor had hidden a whole colony of Alteans to harvest their quintessence. Keith then informed Kolivan of the colony's location while he traveled to warn Team Voltron, but the colony was deserted by the time the Blades arrived.
After the collapse of the Galra Empire following the deaths of Zarkon and Lotor and the disappearance of Voltron, Haggar's druids set out on a campaign of extermination against the Blade per her last orders. Many operatives had been exposed during the temporary alliance with Lotor, forcing Kolivan to recall as many agents as he could and take a stand within a single base. During the long battle of attrition that followed, casualties reduced both sides to a fraction of their former strength.
Following Kolivan's rescue by Team Voltron, Blade of Marmora is currently rebuilding, as at least 5 new members of the group can be seen among those who attending Shiro's speech.
In the epilogue, the Blade of Marmora took over leadership of the Galra Empire, vowing to rebuild it and as a result, the empire officially joined the Galaxy Garrison as allies.
- Ulaz - (deceased)
- Thace - (deceased)
- Antok - (deceased)
- Regris - (deceased)