It's a bit weird with the wayDC treat Mongul; it's a title rather than a name, with each Mongul having to defeat the previous ruling Mongul in combat.
So the current Mongul hasn't done much, but do we take all the previous Mongul feats and say well, current defeated him who defeated the previous one and so on and so forth, and apply ABC logic?
Yeah but that's the thing, they're all different characters. Mongul is just a title.
It's like having Green Lantern in your thread, but not specifying which GL. But not quite a good analogy, because GLs don't fight each other to gain the title 'Green Lantern' - Monguls do.
So current Mongul has defeated the Mongul we saw before, who in turn defeated the Monguls beforehand etc etc. So do we share feats, similar to say, WWH being able to perform the feats 'weaker' Hulks that came before him did?