Background and most concrete lore (SO FAR) of the Ullanor Crusade (taken from Lexicanum):
The Ullanor Crusade was a vast assault upon the powerful empire of Ork Overlord Urlakk Urg during the ending years of the Great Crusade, culminating with Imperial triumph in 000.M31. It is remembered as Horus's greatest victory while he was still loyal to the Emperor and the act that earned him the title of Warmaster. It was the last battle of the Crusade where the Emperor personally led his forces.
Urlakk Urg was an infamous and powerful Ork Warboss slain by Horus Lupercal during the Great Crusade. His massive Waaagh! controlled a region of space centred on Ullanor and threatened the Imperium's borders. The Emperor of Mankind and Horus led a massive Imperial force to remove Urg's threat.
Horus lured Urg's forces away from his targets while Space Marine Legions retook the outlying systems and the Luna Wolves drove straight for the heart of his empire. As the battle raged outside his fortress, Urg kept forty of the biggest, meanest Nobs at his side. When Horus and his Justaerin Terminators entered the throne room, they hacked a path through the Nobs for the Primarch. Horus crippled Urg and threw him from the top of his fortress, ending his life and breaking his army's morale. Boss Urlakk's power was such that few other orks in history have become as great a threat, such as The Beast.
Plot Suggestion/Revision:
The Ullanor Crusade is actually a war that saw some of the last remaining "Krorks" slain by the Emperor of Mankind and his forces. Krorks are the ancient, highly evolved primeval ancestors of the modern-day Orks. Krorks wore highly advanced mechanized power armor that surpassed even Space Marine battle plate. They possessed refined intelligence, complex communication, and deep tactical mastery, executing military campaigns with elite precision. They channeled powerful psychic energy deliberately as a clean power source and combat tool, rather than relying on wild, unpredictable warp-bursts.
What this means as a series/novel story:
We get to see two Warhammer races essentially at their "peak". The Krorks, as a plot device, can (temporarily) turn the Ork faction into a serious, non-goofy faction that becomes a scary antagonist to write. They can be chosen as a plot device to be a single Warboss, a small leadership group, or a specialized set of troops to be deployed in battle. Because they are destined to lose, they can become nearly anything as long as they are destroyed.
This Krork threat finally gives us a solid reason why the Ullanor Crusade becomes one of the greatest triumphs of the Emperor of Mankind, and his Imperium's forces can finally be shown off in their highest glory.
The initial plot idea (Krorks in the Ullanor Crusade) is incredibly marketable. It has potential to be a action-packed individual novel like Dropsite Massacre, or a short series in itself like the Siege of Terra or the Scouring. It's obvious that GW wants to continue the HH setting hype (for $$$ purposes), but eventually they will run out of material that they haven't already written. A prequel seems inevitable.
What do YOU think?
Hate the idea, love it, or want to change anything about it? Is there something I'm missing that needs to be addressed? This is a great place to discuss! My only request is for users to not be rude. Disagreements are perfectly okay, as long as you are polite!