The Sakaaran Guards are supporting antagonists in the 2017 Marvel film Thor: Ragnarok. They are an elite military force acting as enforcers of the Grandmaster, the ruler of the planet Sakaar.
Serving the Grandmaster
Serving as enforcers to the Grandmaster, the Sakaaran Guards share his desire of winning the people's hearts by using different life-forms in a gladiatorial event (known as the Contest of Champions) held in a large arena. Even one of them named Topaz helps the Grandmaster in intimidating his new fighter by handing him his melt-stick to execute another Sakaaran. Even a sole Valkyrie dubbed 142 became one of them following the massacre of the Valkyries committed by Hela.
Facing a Revolution
Following Thor and Loki's exile to Sakaar after being defeated by Hela, the Grandmaster had the Sakaaran Guards to capture Thor while Loki wins the favor of becoming his ally. As the Grandmaster and Loki arrange a fight between Thor and the Hulk, the Grandmaster informs Thor that he will grant his freedom if he defeats the Hulk. Several of the Sakaaran Guards watch as Thor almost defeats the Hulk, but the Grandmaster secretly sabotages the fight to ensure the Hulk's victory, as he has no intention in setting Thor free.
Eventually, Thor manages to escape from confinement and freed the Hulk from the Grandmaster's control by using a recording of Black Widow. Outraged by this, the Grandmaster orders the Sakaaran Guards to capture both Thor and the Hulk, but after reliving the deaths of her fellow Valkyries (thanks to Loki's magic), 142 decides to help Thor in defeating Hela and her army of Berserkers, since Hela was the one responsible for the massacre of the Valkyries. 142 even captured Loki to prove her goodwill, though Loki decides to ally himself with Thor to save the Asgardians from Hela's wrath. To that end, Loki aids Thor in taking down several Sakaaran Guards to their deaths and freeing several gladiators from confinement. The gladiators would then form a resistance against the Grandmaster and the other Sakaaran Guards while Thor and his friends head back to Asgard to defeat Hela and the Berserkers.
Following the destruction of Asgard and the deaths of Hela and the Beserkers (at the hands of the fire demon Surtur), the Grandmaster is last seen being confronted by the surrounding rebels, which might imply that they have defeated and killed all of his Sakaaran Guards for good. Realizing now that he's surrounded, the Grandmaster tries to take credit for the revolution, but the rebels are not convinced by it, much to his dismay.