ITT a guy named CorvusCorax posts in a thread about your favorite primarch.... doesn't say Corax

Indeed, this is true.

Back on topic: I think Lorgar (after the Dropsite Massacre) or Curze for traitors, and for loyalists it'd be either Guilliman or Corax.

Dat timing Trae, dat timing.

You think you can stop me? There are TWO Corax's on this board!!! MUAHAHAHAHAHAA!
No, really, there's another dude named Corax I just saw somewhere. Teetle leetle.

Sanguinius.

Courageously fought a traitor powered by the 4 chaos gods prior to curb stomping a legion single-handed for 7 days.

No wonder there's Sanguinala.

Guilliman; because without him their wouldn't be the Imperium that we know today.

for the Lion!!!

I'd say, Ferrus Manus, just because FLESH IS WEAK

Vulkan. Cant die and is known for being captured by and frustrating Chaos. One day our Primarch will return to his rightful place amongst the Salamanders.