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After the final boss of the Forest of Echoes mission, the Corrupted Techeun, has lost a third of its health, it will create an immunity shield around itself and teleport to the far left side of the arena. After this, three Hoarfrost Executioners will spawn by the boss. They come armed with Boomers that are imbued with the power of Stasis, which will slow you down if hit by their projectiles, and freeze you if you take too many. The Executioners must be killed in order to lower the Techeun's immunity shield so that you can continue to damage it. After it has lost another third of its health, the boss will teleport to the far right side and three more Acolytes must be killed before you can finish it off. When playing the activity on Legend difficulty, the Executioners will spawn with Void Absorption Shields for extra defense.
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