Having worked our way from imaginary epic super-battles from land to air, could you doubt that sea was far away?
{democracy:142}
So slip on that swim suit and let's get moist!

- Aquaman: I pick on poor Arthur quite a bit, and I confess that's mostly due to my earliest impressions of the character coming from incredibly lame "Super Friends" episodes when he'd die after an hour out of the water. Nothing intimidates an enemy like the sight of a super hero toting around an emergency spritzer. But since this all-out slugfest we're imagining would take place under water in the first place, that's not really a concern. And given that, Aquaman is clearly a stud. Strong, fast, cunning, and with the ability to command sea creatures, it's easy to see why he's King of the Sea.
- Namor the Sub-Mariner: Of course, there's a King of the Marvel Sea as well, and he's arguably even tougher and wilier (is that a word?) than Aquaman. He also matches Arthur on the silliness scale with those inane ankle wings. However, as we said, this is under water so the wings don't really enter into it. However, you have to consider the awesome power of the scaly Speedo, an item of clothing so intimidating it has been known to knock air breathers right on their rumps.
- Abe Sapien: While he's looking about quizzically and trying to empathize, Namor would put his fist through his skull.
- Marrina (Alpha Flight): She actually fought Namor a time or two when her alien nature got the best of her, I think, so she's not the pushover you might expect from the big eyes and cute smile. Depending on the time of the month, she could be a real contender. And I am about to get slugged by my wife for saying that. OUCH!
- The Man From Atlantis: Patrick Duffy followed in the tradition of Keith Carradine by never actually using his abilities until the last possible second, and then for literally just that second. He did have the whole under water whole-body seizure swimming technique down, however. He should've stayed in Dallas, though, because in a fight any one of the other people on this list would use him and his white-guy afro as a towel.
- Triton: Another Marvel hero, this member of the Inhumans sports the nifty head fin any serious scaled savage needs to be taken seriously.
- Stingray: Just a guy in a suit, but ask Tony Stark -- guys in suits can rock.
Honestly, the two main names are Namor and Aquaman. And I'd be honestly curious to see how a fight between them would shake out. In general, DC characters tend to have more raw power, but Marvel characters tend to have the will to use what they've got more ruthlessly. I'm pretty torn on this one, unsure which way to go. I get caught up between the scaly Speedo and the scaly orange tunic, hard pressed to say which is more ridiculous.
So I'm going to just roll the dice and say Namor, because I love his hair cut.
How about you?
Has to be Abe, if he can harpoon Rasputin then he can win an underwater Battle Royale :L
Stingray. Aquaman can take down the others with his mind powers, except Stingray. When Arthur has the other down for the count, Stingray can manhandle Aquaman.
While he’s looking about quizzically and trying to empathize, Namor would put his fist through his skull.
I literally LOLd.
Aquaman, cuz he can call on beluga whale reinforcements.
Out-RA-geous!
Namor has the sheer power and speed to take anything Aquaman or anyone else could through at him. We’re talking about someone able to hold off the entire Fantastic Four, after all.
Wait a minute. Does the Warlus swim underwater? If so, then all bets are off.
I chose Aquaman just because nobody chooses Aquaman, and you get to where you feel a little sorry about that, but you still don’t want him on your team.
Have you SEEN Marrina with the Fangs and Claws out?
SCARY!!!
Oh, sure. I bet if he was WHITE Manta, you would’ve included him.
I went with Namor, mostly thinking of Ultimate Sub-Mariner. That dude would win hands down.
And then he would go find and molest Sue Storm.
It’s funny you mention the general power difference in power levels between Marvel and DC, because the underwater characters are the exact mirror image – Sub-Mariner is significantly stronger and more durable than Aquaman. (Namor’s skin is thick enough to bounce handgun bullets.) But – Aquaman telepathically commands sea-life, Namor does not. that wold make it interesting. In the actual battle between Aauaman and Sub-Mariner, Arthur managed to evade Namor’s fists just long enough to set him up for a Killer Whale to land on him. (Which only immobilized Namor just barely long enough to qualify as a win by the rules of that specific contest.) But they seemed to be implying that their physical abilities were close, and they are not. Arthur could barely bench press a full U-Haul, Namor can easily bench press a tank or a full passenger train car. So, I had to vote for Namor in any full out slugfest.