DragoMorph

This is a bunch of Batmen and Jedi vs eight two-ton nigh-invulnerable bullet-timing ninjas. The Spartans might damn well speedblitz, Cortana can effectively take control of the Citadel very quickly, and the Arbiter is invisible. The biotics are powerful, yes, and it's a fight if it's at a distance, but they're not going to stop all the Spartans before they can close the gap. They can also straight tank the Mass Effect weapons if they just charge them (they'll need longer than a Spartan's sprinting to take down their shields and get through their armor), and with the way the Spartans fight, even one or two can manhandle the Mass Effect crew in CQC.

And that's just an open fight between the Spartans and the ME crew. Add in the fact that the Halo team are incredibly stealthy (the Halo games are pretty severe "one-man-army" exceptions, in most of the EU material the Spartans never even get seen, especially the S-III's), plus can take over Citadel systems with Cortana, and can bring straight up heavier firepower, I think the ME guys are just outmatched.

Looks good, I just don't like the fact that Batman is standing in the forefront on artwork for Superman's movie.

Is this supposed to be the Amazing Goblin?

Doesn't matter either way, speedsters are disqualified as per the OP.

This is a weird sort of battle. I notice with speedsters it's only ever a binary situation, either one or the other is a clear victor, unless they've both got speed or some speed counter. Essentially, I'm looking for a character that has the most even match-up against the New 52 Flash but without that character's power-set being tailored to counter the Flash's and ONLY the Flash's (so no pure speedsters, no one who can bring an anti-speed suit), though guys like Captain Cold who can slow the Flash down as a side effect of his main power-set are cool. Assume a random encounter, but you can make an exception if you have someone in mind who would just need foreknowledge that they're fighting someone, but that someone is unknown. Also assume that the person has up to five seconds of notice that they're up against Flash.

The Flash is in-character, morals on. The other guy ideally will be in-character as well, but can be in any state of mind necessary.

Well, considering this is a master Waterbender versus a paraplegic, I'm gonna have to give this to Katara.

Eight creatures, each individually four times stronger than a guy who blew up the moon, versus a rhino and a strong guy with four arms.

On the subject, American History X was a fantastic film.

The Flood can infect Reapers, through the logic plague. Or at least it's possible, whether or not the Reapers can resist is part of the debate. Based on the fact that Forerunner tech couldn't resist the logic plague, I'm going to say that the Repaers would have a tough time. The other thing to consider is that the Flood might use up the organic resources of the Reapers; if they're immune to indoctrination, then one of the major advantages the Reapers have is out the window.

The Flood versus the Reapers. Set in the Mass Effect universe, due to the technical constraints on how the Reapers work. The Flood show up just after Sovereign is defeated, giving them a few years to do their thing before the Reapers hit the scene. If that's not enough, how much additional time would they need before the Reapers show up to be prepared? Combatants have no prior knowledge of each other as both are extra-galactic threats.

360 degree field of pure laser death when Starkiller decides to start spinning his lightsabers. Plus, good luck sneaking up on a Jedi. Also, why exactly can't Starkiller cut up Alex just like Heller did? Now you're the one with the baseless assumptions.