Wow, the Hulk army is out in force! Should we really be debating who's stronger? takes more than just brute strength to win a fight.
All three of these guys have brute Strength in spades! but Kurse is a better fighter he was the Dark Elves champion before the Beyonder turned him into Kurse, hes an Immortal with centuries of combat experience, hes twice as strong as Thor without any amping.
Mangog IIRC feeds off negative emotions, like for instance anger?so as Hulks rage goes up, Mangog also gets stronger.
Mangog is also powerful enough to worry Skyfathers, so I would say in this fight, merely being the one who can lift the most weight, isn't going to win you this fight.
I have to say they all have a chance at victory here but I would say Mangog would take the majority.