Mark of Conquest?

[Sephiroth_Lionhear88]

i read something about the mark of conquest in the item list and it says something bout a strong warrior please enlighten me cause i ain't got a clue what the hell that's all about

[NashX]

The Mark doesn't actually "do" anything. But it shows that you're one hell of a fighter http://cosgan.de/images/more/bigs/a084.gif

[Old Manus]

It means you've beat Nemesis.

[Auronhart]

It means you've beat Nemesis.
Yeah, it's like the "proof of omega" in the tutorial if you beat omega weapon in ff8.