Spoilers: Character background and the game's Bonerattlaz presentation; no campaign ending.

Bonerattlaz in Total War
In Immortal Empires, Azhag leads the Bonerattlaz. Total War: Warhammer, the first game, is the ownership route, shared with Grimgor. The campaign uses the race's Waaagh! and Scrap. His own job is the extra one: Death magic on top of an orc who still fights in the line, and the wyvern Skullmuncha once the campaign gives him that mount.
A flying lord can reach a threatened flank and can also sit under missiles. The play page treats the infantry as the engagement and the wyvern as the choice that follows. That is the game's Azhag. It is a sandbox warboss with a crown, not a script of where the crown was forged.
The iron crown
The game's biography gives Azhag an unusual tactical mind. He uses words other greenskins do not understand. His eyes glow. He falls into trances and argues with himself. The iron crown is rumoured to be an age-old relic of ancient evil. In that telling it is a dark communion, and it is the source of the foresight and the guile.
The rumour stops at the relic. Followers put up with the strange behaviour while the victories continue. Grimgor, from the same base game, is the Black Orc who wants another battle and nothing the crown is selling. Wurrzag is a shaman of Gork and Mork. Azhag's spells are Death.
Other greenskin lords
Skarsnik's war is Eight Peaks and goblins. Grom cooks. Gorbad writes Da Plan and rides Gnarla. None of those campaigns is a chapter of the crown's communion. They share Orc Boyz, Night Goblins, Waaagh!, and Scrap, then split on the lord's own tool.
Snagla Grobspit can join a Bonerattlaz army when the Gorbad pack is owned and his mission is done. He is a hero, not a second crowned warboss. A battle the player wins with Skullmuncha is this campaign. It is not a date in the rumour about the relic.
Azhag the Slaughterer: gameplay and availability · More character stories
Sources
- Azhag the Slaughterer — wiki.totalwar.com
- The Greenskins — totalwar.com
- SEGA Immortal Empires ownership guide — support.sega.com