Hawkeye #4 (1983)

Waking up in the basement of a mortuary, Hawkeye and Mockingbird find out that they have been captured by Crossfire, and he was the one who hired Silencer, Oddball and Bombshell to attack the two heroes. Crossfire then reveals that he plans to kill Hawkeye and arrange it that at his funeral he will brainwash all the heroes that attend into fighting each other to the death. Then Oddball and Bombshell take Hawkeye and Mockingbird into a room so that Crossfire can test his brainwashing machine, called the Undertaker Machine, and make the two heroes fight to the death. Hawkeye and Mockingbird share a kiss before they are forced to fight. Crossfire switches on the Undertaker Machine and the two heroes begin to fight. Crossfire switches off the machine to see how long the effect takes to wear off. During this moment, Hawkeye puts a hyper sonic arrow head in his mouth, unseen due to some cameras being damaged in the fight, to nullify the ultrasound Undertaker's effects. It works and Hawkeye manages to knock Mockingbird unconscious before seemingly falling unconscious himself. Oddball and Bombshell pick up the two heroes, but Hawkeye manages to subdue them before going after Crossfire. Crossfire knocks himself out by trying to shoot a concussive arrow at Hawkeye but failing and thus exploding on the ground next to him. When the police come to arrest the villains, Mockingbird tries to get together with Hawkeye but he dismisses her, not knowing what she said, because he was rendered deaf from the hyper sonic arrowhead. Fortunately, Mockingbird catches up with Hawkeye and realizes what's happened and gets Clint a hearing aid. One week later and the two heroes have become an item and are taking a break in a cottage in the Pocono Mountains in New York.