Lieutenant Thace is a soldier of the Galra Empire working under Commander Prorok. He mysteriously enables the Voltron team to escape during their attempt to rescue Princess Allura from Zarkon's Central Command, with everyone left unaware. Thace is actually a spy working for a rebel Galra faction called the Blade of Marmora. After Prorok is suspected of Thace's actions instead and taken away to become a Robeast, Zarkon promotes Thace to the rank of Commander and places him in charge of investigating for spies within the Empire.
Unfortunately, Thace is cornered by the investigations of Haggar and her Druids, and is brutally tortured for information; the rebel refuses to crack under the pain, and escapes his bonds to assist the Voltron Team in disabling power on Zarkon's Command Ship by detonating the Central Hub. His attempt is successful, but Thace willingly dies in the resulting explosion.
|Blades||Antok ◆ Keith ◆ Regris ◆ Thace ◆ Ulaz|
|Team Voltron||Allura ◆ Coran ◆ Hunk ◆ Keith ◆ Lance ◆ Pidge ◆ Shiro|
|Galra Empire||Acxa ◆ Beta Traz Warden ◆ Ezor ◆ Galra Commander ◆ Haggar ◆ Haxus ◆ Ladnok ◆ Lotor ◆ Morvok ◆ Narti ◆ Olkarion Commander ◆ Prorok ◆ Raht ◆ Sendak ◆ Throk ◆ Trugg ◆ Zarkon|
|Blade of Marmora||Antok ◆ Kolivan ◆ Regris ◆ Thace ◆ Ulaz|
|Galaxy Garrison||Iverson ◆ Matthew Holt ◆ Samuel Holt|
|Arusians||Arusian King ◆ Klaizap ◆ Moontow|
|Balmerans||Shay ◆ Rax|
|Mer||Blumfump ◆ Florona ◆ Luxia ◆ Plaxum ◆ Swirn|
|Olkari||La-Sai ◆ Lubos ◆ Ryner|
|Other Aliens||Alfor ◆ Baujal ◆ Myzax ◆ Nyma ◆ Olia ◆ Ozar ◆ Rolo ◆ Remdax ◆ Sal ◆ Slav ◆ Te-osh ◆ Vakala ◆ Varkon ◆ Xi|
|Other Humans||Colleen Holt ◆ Keith's Father|
|Robots||Beezer ◆ Rover|
|Aliens||Altean Scientist ◆ Hira ◆ Slav|