The Mythrol is a blue-skinned quarry played by Horatio Sanz, the target of the very first bounty in The Mandalorian. He talks continuously, negotiates badly, is frozen in carbonite for the journey, and reappears in the second season working off a reduced sentence as Greef Karga's bookkeeper on Nevarro.
His function is procedural: through him the series demonstrates the puck, the fob, the carbonite chamber and the Guild payout before it explains any of them in dialogue. He is also the show's early signal that the people being hunted are not, generally, monsters.
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