@senglord: I think you're underestimating Prometheus. Prometheus has an intellect greater than Batman, prep better than Deathstroke, and accuracy on par with Green Arrow, not to mention a gigantic variety of weapons ranging from mini-rockets to molecular darts. To top it all off, his physical stats are already on par with Batman and he created a helmet that can download information, including all the fighting styles and moves of the thirty best martial artists in the universe. For every plan he makes, he goes over every possible scenario, thousands, making sure his plans succeed. He's incredible at prep, taking on groups of Justice Leaguers, even better than Deathstroke taking on groups of Titans. You know how they defeated Prometheus? They downloaded Stephen Hawking's disease (can't remember what it's called) into his helmet and Martian Manhunter did something with his mind (can't remember details) because they knew he could easily escape from prison and try to defeat them all again. Seriously, not many people can face Lady Shiva and live to tell about it. This guy mopped the floor with Shiva in three seconds. With prep, he could take the entirety of team 1 by himself. He could probably hold his own against everyone on team 2 combined with prep excluding Black Manta. He even murdered the other guy that took his costume, claiming he used his equipment badly. I think he would survive longer than Deathstroke, especially since he's impressive at analyzing people. I honestly think that it depends on how many assassins and if they're notable or just normal.
I absolutely agree with you about Black Manta. Someone said he was a street leveler. -_- Please, he trades blows with Aquaman, who can lift 100 tons easily. I think Batwing's the weakest of the three though. The only possible factor that I haven't accounted for is that the Bat family's teamwork and coordination is better than everyone else's but I don't think it will make up for the difference of firepower. I think Prometheus could survive until it is Black Manta and Blade left because I'm almost positive he can defeat any individual on each team excluding Batwing, Black Manta, and Blade. Seriously, he's got some serious firepower with mini-rockets, wrist gauntlets, and microscopic nanobots.