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The Battle of the Ywllandr system was a battle fought during the Outer Rim Sieges of the Clone Wars.
Jedi Master Plo Koon led a strike force of the Republic Navy against the Confederacy of Independent Systems in the Ywllandr system. Koon directed his fleet against the Separatist choke point from aboard the Venator-class Star Destroyer Courageous. Shortly after, Koon departed for Cato Neimoidia.
- Star Wars Episode III: Revenge of the Sith novel (Mentioned only)