I don't think there is an undoubtful ranking between all Primarchs, even in a specific domain. This is just my own feeling, and the difference between many of them could just be a tie.
Originally Posted by Angel of Blood
Angron beat Guilliman? You mean Angron and Lorgar beat Guilliman, who was still holding his own against both of them for a while.
Lorgar is one of the weakest (maybe "the" weakest) in melee (he hit an unaware Guilliman to the ground, but I'm pretty sure he would have lost a real ensuing fight).
And I'm also pretty sure that Angron beats Guilliman, because the melee is his key domain. Guilliman strategy and thinking is not much use against blind fury at close quarters (Angron would have crushed Kor Phaeron in less than 2 moves, according to me).
As Monty said for 8 and 9, where do you get that Mortarion slightly best the Khan.
How is the Lion average?
Because, for me, he's not in the top 6 (but maybe close to it, like Guilliman, and maybe above the Khan and Mortarion ... it's difficult to make a real hierarchy between those of the average group).
Also for 11. Whilst I agree that Perterabo isn't amongst the top tier, he had been drained of all his energy by the stone Fulgrim 'gifted' him beforehand. His actual life force was being sucked into the stone for Fulgrimd use.
Sure. But Fulgrim (and his legion) is a duellist by nature, where Perturabo is a tactician (playing chess or the wargame of the attack of Terra, I would say the opposite, of course).
14. Saying Corax was in anyway beaten by Curze is also one of those that gets floated around. Corax had just brutally beaten and envicerated Lorgar, and would have killed him had Curze not intervened. Corax is smart, he's already been fighting desperately on Istvaan V even before the second wave, he's then slaughtered his way through the Gal Vorbak and Lorgsr, but now is up against a fresh Curze and can see his men getting slaughtered. It's either pull back and help his men, or fight Curze, who is fresh, watch his men get slaughtered more and have Lorgar rejoin the fight if it takes too long.
How higher would you put Corax in such ranking, then ? Above Curze, I would agree ... they are in the same category for me : good fighter, but their true strength relies out of the direct hand to hand fight (stealth, hit and run, ambush, ...).
As for Alpharius, it's very, very unlikely he was killed by Guilliman. Everything about Eskrsdor screams Alpha Legion manipulations. But more telling, the whole account was told by an Inquistor who later fled after being suspected of being an Alpha Legion agent. The Ultramarines themselves are sceptical about Eskrador.
Who knows ?
What remains is that Alpharius, by nature, is not oriented towards direct close combat, and that he is shorter and thinner than the other Primarchs, which helps his Space Marines to pretend being him. Height and weight are both key assets in melee.
I would place both the Khan and the Lion in the upper tier as well.
Above which Primarch of this upper tier ?