In Thor: Ragnarok we have a scene in which Thor is trying to access a computer in a Quinjet by saying his name in different ways. One of the ways is by calling himself "the strongest Avenger", which is unsuccessful. Then when Bruce Banner accesses the computer it says "Welcome, Strongest Avenger".
In the MCU the Avengers team consists of: Thor, Hulk, Iron Man, Captain America, Black Widow, Vision, Scarlet Witch, Hawkeye, War Machine, Quicksilver, and Falcon. A quick break down leads me into a few categories where we can narrow down the potential candidates for "strongest" (these are my own categories and opinion based on what I have seen in the films):
- " Power Level 1", Human with attachments: Decidedly human and mortal and powers come from technology or weapons/martial skills: Iron Man, Black Widow, Hawkeye, War Machine, and Falcon
- "Power Level 2", Mutant/Enchanced: Humans with different DNA or enhanced DNA, powers are "supernatural" but they are still mortal: Captain America, Scarlet Witch, Quicksilver
- "Power Level 3", Non-Human: Decidedly not-human, mutates, or something else and powers "god-like", may be immortal: Thor, Hulk, and Vision
So in my own head the competition is between Thor, Hulk, and Vision.
My question is; is there anywhere in the Marvel canon that can give us an objective answer as to who is the "strongest", or was this just joke (either in-universe by Tony Stark or out-of-universe to make us laugh)? My preference would be within Earth-199999 or, if we cannot surmise an answer there, from Earth-616 (I don't need a different answer from every alternate universe).