Helska IV

The frozen fourth planet in the Helska system, Helska IV, was the cite of the Yuuzhan Vong's first foothold in the galaxy. It was here at Helska IV that the Yuuzhan Vong set their Yammosk, or War Coordinater, under the frozen surface.

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The young Jedi Knight, Anakin Solo, formulated, and excecuted a plan to use a shieldship, and reflect energy back at the planet, thereby stealing the Yammosk's energy through evaporation. The plan worked, and the ice planets liquid core, froze, and then shattered, killing the yammosk, and all Yuuzhan Vong on the planet.