Roy Bivolo

Roy G. Bivolo, nicknamed Prism by Cisco Ramon and later dubbed Rainbow Raider by Caitlin Snow, is a meta-human who was affected by the S.T.A.R. Labs particle accelerator explosion, leaving him with the power to manipulate people's emotions.

Biography
Bivolo was in Central City when S.T.A.R. Labs particle accelerator exploded. The dark matter gave him the ability to control peoples emotions. Bivolo, taking advantage of this ability, robbed a bank and managed to get away by making the crowd go into a fierce rage which was disrupted by the Flash. Joe West, along with other Central City police officers later tracked him to his hideout but Bivolo used his abilities to take control of one of the officers and have him turn on his fellow partners however they were saved by the Flash and the Starling City vigilante the Arrow. The Flash later tracked him down but when he confronted him Bivolo affected him with his powers and escaped, leaving Barry to attack Oliver. He was eventually defeated by the combined forces of the Flash and the Arrow and imprisoned in the Particle Accelerator prison.

Powers

 * Pathokinesis: After surviving the S.T.A.R. Labs particle accelerator explosion, Roy gained the power of pathokinesis, which allows him to manipulate the emotions or feelings of an individual. Through looking at people's eyes, he can control the parts of the brain that house anger through the optic nerve. When this happens, his irises flash red and the victims irises follow suit. He can make anger in people so extreme that that the victim turns homicidal and destructive. Individuals with heightened immune systems and healing powers such as Flash are shown to have a unique reaction to Roy's power. While initially showing no affect, Barry Allen slowly and gradually became more emotional sensitive. He started with being impatient with others' criticism followed by harsh resentment towards them. By the following day, his eyes finally began showing signs of Roy's power affecting him, to which he had no patience for others and easily became confrontational. Ultimately, his anger turned into paranoia and caused him to go into homicidal rage to anyone who he thought opposed him.

Weaknesses

 * Colors: A certain bright color could reverse this effect and it is most likely to be red, as Barry's red blur seemingly reversed others being affected by Bivolo, and red was on of the colors shined at Barry to reverse the effect. Since Barry cannot see the red light he projects when moving at accelerated speeds, he could not reverse the effect himself.

Trivia

 * "Roy G. Bivolo" is a play on the "Roy G. Biv" mnemonic for the visible spectrum of light, (Red, Orange, Yellow, Green, Blue, Indigo, and Violet) hence the nickname, "Rainbow Raider".
 * Using different colours for different emotions may also be a reference to the emotional light spectrum seen in Green Lantern and other related comics.