Good point. If Corax had time to prepare for Curze, Curze would time to prepare for Corax. The poll was so close but I guess all the Night Lord fans showed up.
I think Curze could take Russ in the right situation but I don't see Corax taking Russ for some reason.
Corax would fight a little more honorably. I don't think it ever says if his wraith slipping affects primarchs. Even then, Russ would just sniff him out.
We shall see if Corax and Russ have a show down. I want to lead you guys back to the original post. In my opinion, Corax and Curze are both masters of ambush. I guess it would depend on who could take the initiative and then press their advantage. It's hard to say with such evenly matched Primarchs who would come out on top. To me, Curze, before he lost it, feels a bit like Batman but without the restraint. Corax on the other hand, is a master of hit and run...
Curze was no slouch in combat, as he could stay on toe-to-toe with the Lion, and both of them did mess each other up quite a bit in the Eastern Fringe campaigns. This excerpt from the Warhammer wiki is really well written and depicts the confrontation between the Raven and the Haunter. Corax looked to meet eyes as black as his, in a face as pale as his own. His claw strained against a mirroring weapon, both sets of blades scraping as they ground against each other. One claw seeking to fall and kill, the other unyielding in its rising defence. Where the Raven Guard Primarch’s features were fierce with effort, the other face wore a grin. It was a smile both taut and mirthless -- a dead man’s smile, once his lips surrendered to rigor mortis. It was the Night Haunter. Corax sought to wrench his claw free, but Curze’s second gauntlet closed on his brother’s wrist, so that Corax would be unable to fly away and escape his fate. Curze looked upon his prostrate brother and ordered him to rise from his knees, disgusted at his cowardice. Corax was not idle as this exchange took place. He fired his flight pack, burning his fuel reserves to escape Curze’s grip. The Raven Lord’s claw ripped free, and Corax soared skyward, carried on jet thrust away from Curze’s rising laughter. Curze then shoved Lorgar back towards his Word Bearers.
I haven't read the novel yet but The Lion is not one to be trifled with. I think the fight would be pretty evenly matched. Curze and Corax have such similar fighting styles.
Bare in mind he had just been betrayed by Imperial forces and was witnessing his legion being cut down around him. Not to mention running into daemonhosts for the first time. There are mentions of this in Deliverance Lost that Corax could have taken him in battle, but opted to leave him instead. I believe it was to help ensure his legion survive rather than act out of revenge but I would need to check properly. Also, if we are going to go into general capabilities, let's just consider what would follow later that day: Corax would survive being shot down in a Thunderhawk. He would then single handedly perform a flanking charge upon an Iron Warriors armoured division, killing a sentry by throwing a rock so hard it tore through his gorget. Another Iron Warrior would die thanks to Corax punching a grenade into his chest (something which only slightly numbed the primarch's fingers). He would take lascannon shots to the chest, wield a heavy bolter like a rifle, ignore concentrated bolter fire from multiple squads as an irritation, rip a tank to pieces with his bare hands, defeat a Contemptor dreadnought unarmed and walk through the ranks of several traitor legions unnoticed as he was looking for survivors. No offense, but do we have any examples from Curze which match that?
Not really, because there aren't any novels from his perspective and his alone. I honestly believe that Corax and Curze would be evenly matched. If they could easily been switched, had their fates been swapped, that's indicative of it being so, I'd pressume. The most "awesome" moment I can think of when it comes to the Haunter was his demonstration of his philosophy to Dorn, in which he handed a rifle to a man who had just surrendered on a conquered world. The whole "Obedience must be be instilled through fear" thing, and he had made it clear to his guard that no matter what the man would do, he would not be punished for his actions. The minute Curze turned around, the man shot at him, because he thought there would be no consequences. Curze promptly turns the guy into meat sugar particles, and then kind of waves his arms in a sort of "You see what I have to deal with/what I mean" way.