Y’all can rest easy now.
While discussing casting Lars Mikkelsen as the voice of Thrawn, Filoni slipped that the character has a longer-lasting presence than Galen Erso, one of the architects of the Death Star.
“The character takes shape around the voice. He is dedicated to getting it right, he understands that the character is important,” said Filoni in a conversation with StarWars.com. “His character outlived his brother’s [Mads Mikkelsen], who’s in Rogue One, which is a hilarious inside joke for us.”
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And Filoni’s comments indicate that there are plans for Thrawn in the future, though no one knows for sure what it is at this point.
GUUUUUYS
Star Wars: Dave Filoni Revealed Thrawn Survives Past Events of ‘Rogue One’
A Force Sensitive Phasesixer 