Why Hulk Chose Hawkeye to be the One Hero Who Can Kill Him
The IncredibleHulk is a complex figure in Marvel Comics; his incalculable strength can be a boon if aimed correctly, but too often it results in catastrophic collateral damage. As such, Bruce Banner has created a number of anti-Hulk contingencies over the years. But the most effective yet was trusted to none other than the Avenging Archer himself: Hawkeye.
As a refresher, the plot of Civil War II revolves around a new Inhuman who experiences visions of a possible future. One such vision shows the Hulk standing in a gamma-charred landscape with several key Avengers dead around him. Spurred on by this, Captain Marvel and Tony Stark lead a unified front of Avengers, Inhumans, and Ultimates to Banner's doorstep. As their accusations fly, the doctor's apparent agitation begins to grow, until Hawkeye swiftly executes Banner before he can transform. But Bruce actually counted on this happening.
Related: Hulk Can Use His Powers Without Transforming (& It's Way More Terrifying)
It's revealed that Bruce sat down with Clint several months before the incident and gave him a capsule specifically designed to kill him and staunch the Hulk's emergence so he wouldn't be revived by proxy. In their meeting, Banner tells Barton that the anxiety of not knowing when he might lose control next is too exhausting and frightening a life to lead. He trusts Hawkeye to be his kill switch not just because he's the best marksman in the Marvel Universe, but because he's the one most likely to suppress his conscience and do what needs to be done. And though Clint initially takes offense, Banner's read here is justified. This took place in Civil War II #3 by Brian Michael Bendis, David Marquez, and Olivier Coipel.
As Matt Murdock pointedly mentions
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