Just as with regular cavalry, a ridden monster affords its rider an element of additional protection. A character on a ridden monster counts his armor save as being 1 point better than normal (see cavalry in the Troop Types chapter).
Source: Warhammer Fantasy: 8th Edition
Just as with regular cavalry, a ridden monster affords its rider an element of additional protection. A character on a ridden monster counts his armor save as being 1 point better than normal (see cavalry in the Troop Types chapter).