Originally Posted by KRYPTON INC.
The idea that The GOTG were necessary in either an A2 or A3 because THANOS would be the threat never quite made sense to me. Sure, Thanos is an awesome villain, but he is not a known quantity to the GA. Now the GA has embraced the AVENGERS. To have another team show up because Earth's Mightiest Heroes couldn't handle the villain kind of undercuts them. For those that say "but doesn't that show what an incredible and dangerous villain Thanos is?", all I have to say is whose name is the title? That's right.... MARVEL knows not to undercut their heroes.
I don't regard a nod to GOTG in a Thanos-driven Avengers 2 as being a case of the Avengers being too weak to handle him on their own. Instead, I see GOTG (the movie and the team) as the story catalyst for Thanos to appear on Earth, and one or more of the Guardians to then cameo in TA2 to give backstory, guidance, and maybe reveal an Achilles heel for the heroes to exploit.
All of that is predicated, of course, on the notion that Thanos *is* the Big Bad in GOTG and TA2, as Jim Starlin said (and I continue to believe). At this point in the rumor and speculation cycle, though, I don't even know if he's going to appear in either one. Would be absolutely stupid if he didn't, but who knows.