They're Everywhere!

Special Attack.
When a Gnasher Herd Breaks from Combat, it is removed as a casualty at the end of step 7 of the Round of Combat Sequence (after taking Break Tests), and all units within 6’’ suffer 1 hit for every 5 Gnashers in the Gnasher Herd, rounding fractions down. Hits are resolved with Strength 5 and Armour Penetration 2.