After the Sinister Six were established in their own movie, it's six against one in "The Amazing Spider-Man 3"! But Andrew Garfield's Spider-Man gets unexpected support: His counterpart from the Raimi films - played by Tobey Maguire - has got into the current dimension and helps him fight the villainous team-up. Actually, the symbiote would be a more appropriate means to give Spidey more strength so he can defeat the group by himself, but in order to avoid repetition, the symbiont is held back for now (more on this later). And let's be honest: two Spideys against Ock & the others looks much more impressive! After the work is done, Octavius ​​and Tobey-Peter leave the TASM universe again and go back to their dimension. Andrew-Peter watches them leave as the portal closes. But with a last pulse he is sucked through the black hole as well! Not even his webs would help him. At this point the film ends ... for now.
The following after-credits-scene would probably work better if we were all completely clueless, ie, if there had previously been no rumors of an MCU-crossover. But maybe it will work anyway to surprise at least some of us: After he was catapulted through the portal, Peter ends up in the middle of a busy street in Manhattan and has to dodge the cars. People stop and look at him aghast. Spidey thinks that he must have followed his counterpart and Ock into their dimension and looks for the two desperately. No trace of them. Just as he is about to swing away, his spider sense is tingles: behind him, a familiar noise can be heard. Suddenly he is knocked out by a metal hand. It's Iron Man! "Leaving so fast, buddy!? You're coming with me!" Before Peter can say something or even defend himself, Iron Man takes him piggyback and flies off with him to the distant Avengers Tower. The scene ends, the masses go crazy, the crossover is started!
Just imagine how much hype that would cause!
Logically and ideally "The Avengers 3" would be the first film of the MCU to feature Spider-Man. As much as I would love to see Andrew next to Robert Downey Jr., this is probably the right moment to realize another rumor of last couple of days: a "soft reboot" and recast.. To avoid this, they could also keep Peter's face hidden throughout the film. Spidey would only be seen with his mask on. It makes sense for the webhead to play a role in this film, if you consider another rumor: it's said that we won't see the original Avengers (ie Cap, Thor, Hulk, etc.), but instead a second, unnamed group. But what could be the content of the film? In my opinion it's "Secret War": The Avengers fighting on another planet! And that's when the symbiote comes into play - as true to the comics as it can get! Maybe this was the reason why the symbiote was cut from "The Amazing Spider-Man 2" initially!? So they can construct a completely different origin for the alien parasite??
After the villain (whichever it may be) in "The Avengers 3" is defeated, Peter returns to his own dimension with the black costume, perhaps aided by Doctor Strange. If they have not recast by this point, it is high time now! The quasi reboot would start with a black costumed Spidey and thus set itself apart from the previous reboot. Without resurrecting dead characters and thus saving the continuity to some extent, the doors are open for many new ideas. Of course, Spidey could jump over to the MCU every now and then if he is needed there, and maybe sometime return with yet another new costume to his world... *cough* Iron Spider *cough*
