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Star Wars Rebels wraps up a strong third season this weekend — and a long-anticipated showdown between Imperial and Rebel forces is here.

The season introduced the Empire's Grand Admiral Thrawn, a fan favorite character from old Star Wars novels known for his enlightened strategic cunning. Thrawn tends to win his battles with brain, not brawn.

But in this clip from the Rebels finale, exclusive to Mashable, Thrawn shows he's not above using fisticuffs when necessary.

The Grand Admiral discovers a Rebel spy in his own ranks — Agent Kallus, an officer who has adopted the codename "Fulcrum" once used by former Jedi padawan Ahsoka Tano.

Now that his cover's blown, the Rebel plan to take our heroes' planet of Lothal is in jeopardy. And from the full trailer for the finale, it seems the Rebels are as overmatched by the Imperial fleet as they are in Rogue One:

The Star Wars Rebels season 3 finale airs on Saturday March 25 — and since the show has already been picked up for season 4, we doubt this is the last we've seen of Thrawn or his opponents.