Griffin Grey

Griffin first met Bart Allen after the events of Infinite Crisis that aged Bart four years. He met Bart when he was looking for a roommate and he got him a job at Keystone Motors. One year later on their way to work they had to walk past all the union    

workers on strike to get to the factory and he started complaining to Bart about the picketers. One of the picketers heard him and got in his face about it telling him that workers have to stick together or they'll all be replaced by machines. Later while working at the assembly line Bart asked him why he acted like he did towards the union workers and Griffin told him that he did feel bad about it but the reason he said what he said was because he felt that the old need to move along and make room for the young. After they got off from work Griffin forced Bart into going clubbing and tried to show him how to pick up women but he was confused by Bart's lack of enthusiasm.

The next day at work Griffin and Bart were caught in an explosion at work, one of the picketers had stolen high-grade explosives and planted them in the factory. Bart was able to save himself by tapping into the speed force and Griffin was saved by Jay Garrick but not before being covered in unknown chemicals. He was expected to be in the hospital for weeks but miraculously healed in just one day thanks to his new powers. Seeing an opportunity to quickly become rich and famous he donned a costume and became The Griffin.  
 
During his first attempt as a vigilante he nearly got a child killed but was saved at the last minute by Jay Garrick. Unfortunately his powers began causing very noticeable physical and psychological damage to him, he was aging at an accelerated rate and he was becoming paranoid believing that he was the only hero needed. He overheard a conversation Bart was having with Jay Garrick and heard him mention that they had a suspect for the bombing. Griffin then tracked him down to his apartment and found that he wasn't home but he also found his plans to blow up a yacht belonging to the owner of Keystone Motors during a party.  
 
Rather then tell the police he instead decided to do it all himself and to make sure that nobody else could help he made a fake phone call to the police giving the false location of the bomber. He found the man in a small boat heading towards the yacht and he killed him. For stopping the bomber he was given 100,000 dollars which he quickly spent on a new car and apartment. To celebrate he took Bart out to go clubbing and they ended up getting into a fight over Griffin's methods of killing criminals and destroying everything to get at them.

At the top of his new apartment atop a skyscraper in Keystone City Griffin began to notice more and more his aging body. Bart approached him and tried to help but Griffin's paranoia caused him to snap at his friend when he told him he needed help and he threw him out the window. Bart was able to save himself by tapping into the speed force and cushioning his fall but Griffin took off before seeing the fate of his friend, Griffin's actions caused Bart to come out of retirement and become the Flash once again.  

 With both Jay and Bart fighting crime at super speed Griffin was left in the dust and became infuriated that they were stealing the spotlight away from him. He was pushed over the edge when he heard the cops making fun of him and he attacked a helicopter in retaliation. After he returned to his underground lair he got the idea to kidnap Jay Garrick to find out his secret of slowed aging. The next morning he kidnapped him and tortured him after he told him that the secret was his attachment to the speed force and that Griffin wouldn't be able to use it. To show that he was a better hero than the Flash, Griffin decided that he needed a major disaster to show the city how great he was and he destroyed the bridge between Keystone City and Central City so he could save the day. When he saw the Flash helping people he attacked him but they were both thrown into the water and Griffin was killed by falling debris.