Eagle Claw Bolt Thrower

Eagle Claw Bolt Thrower is a High Elves artillery unit in Total War: Warhammer II. The High Elves' chief artillery piece can mow down infantry and pierce Giants' hearts.

Description
Eagle Claw Bolt Throwers that not only play pivotal roles upon the battlefield, but also bristle from the sides of Ulthuan's warships and the battlements of her fortresses. Eagle Claws can be found not only in Lothern, but throughout High Elf lands. The weapon's canny design allows its crew to alternate fire modes at will - it can loose single shots capable of disembowelling a rampaging Giant, or clutches of six lesser bolts to mow down massed infantry before they reach the High Elf lines. Such is the skill of The Eagle Claw's Sea Guard crew, and the speed with which they reload, that only seconds separate one deadly volley from the next.

Strategy
Eagle Claws are the High Elves´ only artillery and in theory capable of fulfilling both the functions of anti-infantry and anti-large with their two different ammunition types. In practice, while they can do both jobs, they are not particularly good at either. Single bolts will slowly decimate cavalry and monsters, but they do not have the very high penetration and armor piercing damage of regular or warp lightning cannons. Multiple bolts will shred blocks of light infantry, but they have to be clustered very closely and heavy infantry will not take much damage from them. They can be handy in siege battles to destroy some defense towers and create a blind spot in the killing zone in front of the walls so your troops can safely advance. However, it is rarely useful to take more than 1-2 of them with you. Also: remember to protect them from enemy cavalry and flying units.

Another Opinion:

Eagle Claw Bolt Throwers are not an artillery piece that High Elves can build an army around, they are a supporting unit used aid their core units. Their single bolts do not hit nearly as hard as cannons or other high-end artillery, but they are quite accurate and their projectiles comfortably arc over the heads of infantry so that its rare for them not to hitting something worthwhile during the course of a battle. Other more damaging artillery often have flatter trajectories or inferior accuracy such that they'll have their damage output throttled by a lack of clear shooting opportunities or misses. Eagle Claw Bolt Throwers will rarely lack for a clear shot and will hit. Your spear units may be able to kill a monster by themselves, but will do it more quickly and take fewer losses if they have an Eagle Claw helping them. Likewise, your cavalry will appreciate having their opposing numbers roughed up.

Their multi-shot bolts don't do a ton of damage per volley, but the RoF is good and their arc allows to them be firing almost constantly. Even enemy units in melee with your front line can be hit safely by positioning your Eagle Claws behind the flanks so that they can angle their fire over the melee into enemy units on the opposite flank. Other artillery units usually need to have gaps in the line or be pushed around a flank to continue shooting. The disruption from volleys also has a lot value in slowing down and breaking up the enemy lines' advance, forcing them to endure more missile fire from your archers and causing their units to make contact piecemeal instead of as a unified line. This can create opportunities to march blocking units around the leading enemy units to intercept and pin those that have been slowed down by the Eagle Claw fire. You may then envelop or enfilade their leading units with damage dealing reserves without having to worry about their lagging units hitting them in their flanks (having already intercepted and pinned them).