Robert Downey Jr. mustache Twitter a very important question.

The Iron Manhimself assembled an elite force of very opinionated Twitter users when he put his fellow Avengers co-stars on blast. With some throwback photos, he called upon the forces of the internet, asking them to settle the debate once and for all — who wore it best?

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Some fans immediately jumped into their extremely valid (and slightly thirst-driven) opinions.

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For others, though, the competition was getting a little too hairy. So, naturally, the memes started rolling in.

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Personally, I think Twitter has got this ALL wrong. You want to know who wore it best out of everyone in the entire MCU? Have you forgotten about cameo legend, Stan Lee?

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You heard the man. "'Nuff said."

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