WARNING: The following article contains spoilers for Old Man Hawkeye #11, by Ethan Sacks and Francesco Mobili, on sale now.

Marvel's Old Man Hawkeye has been putting Clint Barton through the wringer, emotionally and physically, as it details his escapades before the events of 2008's "Old Man Logan," by Mark Millar and Steve McNiven. Here, we see Hawkeye going after the briefcase he'd later ask Logan to help him safeguard, with this precursor adventure landing the archer at a decommissioned Weapon X facility in the mountains of Alberta, Canada.

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But instead of focusing on his pursuit of the briefcase and its contents, Issue 11 delivers an even bigger moment. As Hawkeye tries to be a hero one more time, writer Ethan Sacks and artist Francesco Mobili finally reveal how he became blind.

In "Old Man Logan," Hawkeye never divulged much about his blindness, hinting it may have failed due to old age. Old Man Hawkeye started off with his vision waning, leaving reader to assume that, over the course of the series, it would disappear due to natural causes. Of course, whether he's blind or otherwise impaired, we've already seen he's as lethal as ever. But still, curiosity is human nature and at long last, all our questions are answered the cause of his blindness: the mutant Avalanche.

In the facility, Clint and Kate Bishop have to take out Baron Zemo's Captain Hydra, as well as the other soldiers loyal to the Red Skull. Zemo is running a program to create a new breed of super-soldiers to impress his boss, and ironically, the briefcase Clint goes on to wield in "Old Man Logan" is chock-full of the vials of the serum. But as it stands, he's unable to acquire it just yet, with this Captain Hydra choking the life out of him.

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He eventually overcomes the villain with some help from a turncoat scientist who wants the building destroyed, and goes after Zemo. There, he finds a frail version of the villain, who tried to maintain the facade that he was young and fit so Red Skull wouldn't discard him. After a monologue, Clint decides to forego his virtuous and forgiving roots, and shoots Zemo with dozens of arrows as payback for masterminding the Thunderbolts' betrayal and the slaughter of the Avengers.

However, just after that happens, with Kate busy trying to destroy the facility, Avalanche ambushes Hawkeye. Using his abilities to create shockwaves, he plants his hands firmly on Hawkeye's skull, and detaches the optic nerves, leaving him blind. It may not be bloody, but it's sure brutal, because we've never really seen Avalanche as unhinged and spiteful as this in years of X-Men comics. It's sweet revenge for killing Zemo, who saw a leader in Avalanche and regarded him as someone who deserved more time in the spotlight.

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With his mentor dead, Avalanche has taken away Clint's most valuable prize, and is now set to turn his gaze on Kate. Only time will tell how Hawkeye reacts to this, but as it stands, we finally know why Hawkye went blind. And as unlikely as the source was, it definitely feels organic to this story, where villains you wouldn't expect to make huge impacts certainly end up leaving lasting impressions. Unfortunately for Hawkeye, that impression is permanent, and changeds his life forever, and -- as we'd read in Millar's story -- for the worse.