Guy Gardner wasn’t “the one, true Green Lantern” he claimed to be; and he certainly wasn’t the most well-liked member in the Green Lantern Corps or ally of the current Justice League. But this hot-headed hero proved he wasn’t a bad fighter when he helped the Corps and the League protect the Guardians from an attack on Oa by the Brood. Still not a likeable guy, Guy was forced by the Guardians to stay on Oa to be thought some manners.
*For spoilers, highlight the below text.*
In 2076, Guy was assimilated by a Psycho Slayer and helped the Monarchs attack Oa. As Psycho Guy, he almost beat Cole Evans to death, before John Stewart stopped him.