Griffin Grey

Griffin Grey (1997–2016) was a meta-human who had super strength, but that same strength left him with accelerated aging.

Particle Accelerator Explosion
Griffin was 16 when the S.T.A.R. Labs particle accelerator exploded, and he was given super strength by the blast. However, he soon found that the powers came with accelerated aging.

Finding a Cure
Grey kidnapped Harry, took him to the Central City Amusement Park and tried to force him to change him back to his younger form and reverse the particle accelerator's actions. Even when Wells explained he couldn't do it, Grey threatened to kill him. Later, Grey broke into a chemical factory, and when Barry Allen, Joe West and Cisco Ramon showed up, Grey began throwing barrels at them, intent on driving them out. He threw a barrel at Barry and succeeded in hitting him, but then aged much more than his previous form.

He later watched Wells work while he was working, and gave Griffin a drink that he told him was the cure. However, Griffin wised up to the trick, and then punched Wells. Then he saw the Flash on the security monitors and walked down to meet him, also throwing a barrel at Joe. He then repetitively punched the Flash, while aging constantly to the point he died of old age.

Powers

 * Super strength:  Due to the functional myostatin in his cells being essentially gone, Griffin was so strong that he was able to effortlessly crush rock and metal objects, as well as lift objects as large and heavy as metal barrels or bumper cars as if they were weightless, and through them across the length of a warehouse. He was even able to take the full force of a van, while he only left behind slight traces of blood.
 * Super Agility: Due to the particle accelerator Grey has gotten the ability of being agile, this is seen when Barry tries to shoot Griffin and quickly dogges and taunts Barry saying "To slow".

Weaknesses

 * Accelerated aging:  While Griffin was super strong, it also had a side effect that he would age a little bit every time he used it. The more he exerted himself, the faster he aged, which is due to his protein in his DNA being ravaged by oxidants and him suffering from oxidated stress. This side effect had progressed so far that, while Griffin was chronologically 18, he looked as though he was in his mid 30's after a year with his powers, eventually reverting to an old man.