A/N: I have absolutely no explanation for this...
Disclaimer: I do not own the Avengers. However, I do know a thing or two about the cloaked figures... :D
Hulk-
Hulk leapt off of the Helicarrier at the plane that was attacking him. Unfortunately, he misjudged the distance and fell. On the way down, he turned back into Bruce Banner. He then died on impact.
Iron Man-
Tony was flying in his Mark VI suit. Unfortunately, it was pretty worn out and shut down.
"Why did I not see this coming?" He asked no one in particular. He then fell and died.
Thor-
Thor was flying using the power of Mjolnir. He was thinking of all the awful things he was going to do to Loki when the hammer suddenly started to fall.
'You are unworthy', he heard in his head. Unfortunately, the hammer landed on him. You can imagine the result.
Hawkeye-
Clint was riding in the back of a Quinjet as it approached the Helicarrier. He fingered his bow and then froze when he heard a click.
He paled. "Oh dear..."
One of his explosive arrows blew up, taking the jet with it.
Black Widow-
Natasha was tied to a chair, being interrogated. Well, apparently. She was actually the one doing the interrogating. She then jumped up and knocked all of her captors out with her ninja-spy skills. Apparently, even ninja-spies can lose their balance because she did, falling to her death.
Nick Fury (I know he's not really an Avenger, I just want to kill him for some reason)-
Fury was watching the battle in New York from the safety of the Helicarrier, like the coward he is. Suddenly, a cloaked figure appeared. "Mwahahahahaha!" It cackled. And then it pushed him out the window.
"Defenestration!" Another figure yelled. She (you could tell by the voice) then pulled out two katanas, slicing the head off one agent and spilling the guts of another. "Decapitation! Evisceration!"
Maria Hill died from a grenade. Phil Coulson survived being stabbed, but was unfortunately too close to the hole left from the glass cage and got sucked out of the Helicarrier.
A/N 2: I know I left Steve out... but that is because his dumb way to die was way longer for some reason and will be its own chapter!