Besides Reaper indoctronation, the Mass Effect baddies don't stand a chance in hell against people like Galactus, Thor, and Hulk. Can a Reaper even kill people like Wolverine? --- http://www.myspace.com/xtreme65
Marvel heroes take out threats like the reapers, much less cerberus and the geth, on a regular basis. Putting anything at all against Marvel is just unfair, as it has some of the most powerful heroes to ever exist. To put it simply, they'd be "overpowered".
You don't even need to enlist the superheroes, just take every Marvel mutant and you'll be fine. Magneto alone would destroy the entire Geth race, let alone an Atlas, and hell, Cerberus as a whole too (they use metal guns, and he'd have a field day with those riot shields).
The thing is, the Mass Effect universe doesn't have "super" heroes by Marvel's sense. It's just humanity versus these threats, and that's why they struggle. If they had super beings, akin to Thor or Hulk, then they'd have much less of an issue. --- July 18, 2011. Megaman Legends 3 has been cancelled. Today, I mourn. Here remains a reminder of what could have been. PSN:ChocoboDreams