Day 1 of Kurganposting until Surtha Lenk is announced (nah, just kidding)
Surtha Lenk is a Kurgan Chaos champion who took part in the great Chaos invasion under Archaon. In the End Times, he doesn't do much before being slain by Valten, but in both Storm of Chaos and WFRP third edition, his host smashes through Kislev and invades Ostland.
I know that the chances of him making it into the game are basically zero. Still, I really wish we had a LL with a horse archer playstyle, viable into late game. All horse archers currently in game are super fragile and don't have armor piercing, and outriders aren't horse archers. In lore, the Kurgan, Hung and hobgoblins fit this kind of warfare; the Kislevites used to but their modern armies have fewer horse archers, used as scouts and light skirmishers.
Surtha Lenk face from the SCM Tribes of the North mod.