Raven Heralds (Repeater Crossbow)

Raven Heralds (Repeater Crossbow) is a Dark Elves unit in Total War: Warhammer II ' s downloadable content, The Queen and the Crone. The Raven Heralds appear from nowhere, leaving piles of corpses in their wake.

Description
In the grim days when armies of Daemons besieged Ulthuan, keen-eyed messengers from Nagarythe kept guard for any signs of a daemonic intrusion. These Dark Riders wore cloaks of black feathers, invoking the raven-headed god Nethu to keep them hidden from the eyes of the enemy. During the civil war, the Dark Riders earned a more sinister reputation. They travelled ahead of Nagarythe's hosts, sowing terror and confusion wherever they rode, burning villages and driving their people into the wilds. In battle, Dark Riders take delight in skirting the enemy flanks to attack war machines and cut lines of supply. They revel in the prospect of running down terror-stricken victims, dragging out every moment of wild panic as long as possible before delivering the final heart-seeking strike.

This unit is possibly inspired from the regiment called the Ravenspears in the lore:

Nowhere had Morathi's influence spread so deeply as amongst the dark riders of the northern wastes. The Ravenspears were one of five patrol-hosts meant to be standing sentry north of the Naggarothi watchtowers, there to seek out incipient danger and carry word south to Naggarond. However, when Morathi foresaw the Bloodied Horde's invasion, she suborned the Ravenspears to join her own garrison at Ghrond, thus denying Malekith of warning even as she strengthened her own position. Now the Ravenspears served Morathi, as so many did, out of equal parts fear and ensorcelled love. So profound was the spell that most did not even recall the lives they led before the Hag Sorceress' gaze fell upon them.

Strategy
The notable upgrade between this version and the standard one is that the riders are now flying. This enables a greater degree of mobility, but does limit the damage output as there are fewer models. When set against enemy lords on large mounts or large monsters in general, they can produce significant damage.