These reddish-purple and yellowish-orange villains were strange anomalies amongst their craven comrades of the day.
The Invisible Destroyer was an energy manifestation of Doctor Phillips, himself a physicist who conceived of the concept that made up his alter ego. Jack Dold was a two-bit crook who happened to inadvertently become the recipient of vast cosmic power, becoming the Mastermind.
While the Destroyer needed to raid plutonium facilities to absorb atomic energy from Coast City, needed to sustain his being, Mastermind out of an act of vengeance attempted to generate atomic energy to destroy Gateway City. Thankfully, the timely intervention of Earth-One's Green Lantern and Earth-Two's Spectre defeated Invisible Destroyer and Mastermind, respectively. While the former, in his disembodied costume, resurfaced during one of the Key's schemes versus the Justice League, Jack Dold's alias stayed on the shelf indefinitely.
Another one-hit wonder like these twin terrors were also a pair of malcontents. Only, instead of having superhuman powers, they relied on devices that augmented their own athletic abilities to pose as much a threat to the Green Lanterns. Assuming the aliases of Javelin and Juggler, these yellow and blue clad crooks had a bout with the Emerald Crusaders as well, defying gravity through technology and tenaciousness to perplex their adversaries, if only for a time. Such is the lot of these B-list bad boys.