14. The Star Wars Homage
Kevin Feige confirmed in the run up to the release of Avengers: Age Of Ultron that his love of Star Wars has bled into his control of the MCU in a very specific way.
"I’m obsessed with Star Wars - and it didn’t start out as intentional, but it became intentional, including that beat that you referenced. It sort of happens in every Star Wars movie, but I was sort of looking at it, ‘Okay, is Phase Two our Empire Strikes Back?’ Not really, but tonally things are a little different. Somebody gets their arm cut off in every Phase Two movie. Every single one."
Andy Serkis' Ulysses becomes the fifth character to lose an arm in Phase 2 (with the Ant-Man arm-loser not yet confirmed), when Ultron completes his new origin by accidentally cutting his arm off.
Whether that means he's going to actually come to Black Panther equipped with his sonic weaponry augmentation remains to be seen, though.