10 Times Green Arrow Has Killed
2. Prometheus - Justice League: Cry For Justice #9 (2010)
The apparent death of Batman and Martian Manhunter during Final Crisis took a heavy toll on the Justice League. Enraged, Hal Jordan insisted that tragedies like this could be avoided if the team sought out supervillains before they committed crimes. After several members rejected Hal's proposal, Green Lantern stormed off and created a proactive superteam with Starman, Atom, Supergirl, and Green Arrow.
During this time, a master mercenary called Prometheus planned a crime spree on a global level. As he initiated his master plan, the deadly assassin killed several superheroes, infiltrated the League's headquarters, and ripped off the arm of Green Arrow's ward, Roy Harper.
Although he was subdued, the League didn't realise Prometheus had placed a bomb in Ollie's home, Star City, and his antics were a mere distraction. While he was being interrogated, Prometheus' bomb detonated, slaughtering millions, including Roy's daughter, Lian.
In Ollie's mind, Star City's destruction proved Hal's point that the League should have been more proactive. To ensure Prometheus never killed again, the archer ambushed him in his lair and shot an arrow through his skull.