The bulk of the War Hydra makes a great shield for the Beastmasters that drive it, protecting them from arrows and other missiles. When hits would normally be randomised between the models of a unit, such as for shooting or a spell, such hits are not allocated randomly but instead are all resolved against the War Hydra. In close combat, the Beastmasters are adept at using the bulk of the Hydra to protect themselves, so all enemies that can choose to attack them or the Hydra must allocate their attacks against the Hydra.

If the Beastmasters are killed, the War Hydra must make a Monster Reaction test just like a ridden monster that loses its rider. When calculating victory points, the Beastmasters are always ignored - assume that the Hydra was fighting on its own as a one-model unit.

Only the Beastmasters themselves have the skill to control such a ferocious beast. Therefore, no other model may join a War Hydra unit.