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Their negative SPD means they will likely act last on any given round, but this is not guaranteed-bad turn order rolls could mean that an Aberration may go before any low-SPD heroes like the Crusader, meaning it is important to destroy these things quickly. They are completely immune to stuns and debuffs, and have a significant resistance to bleed, but have no resistance at all to blight or being moved.
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If not destroyed in time, they will explode for heavy damage, stress, and blight on one hero, or inflict a party-wide Horror. Crystalline Aberrations act similarly to corpses, and replace any corpses on the field at the end of every other round during battles in the Farmstead.
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