Scarabs attached to a vehicle or a unit with armour locations reduce the Armour Value at all locations by 3 while they are attached. This effect is cumulative; so a Leman Russ Battle Tank with three Scarabs attached to it would have a Turret armour value of 16 from the front (25-9). It does not matter where the Scarabs are physically attached to the tank, since all armour locations are affected equally.
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