Flash (Bart Allen)
The fastest guy on earth is also the shortest lifespan hero in DC Universe. Bart Allen, the fourth Flash, can be put in this category. Bart, the grandson of Barry Allen (the second flash), and the nephew of Wally West (the third Flash), live his life as the fourth Flash only in 13 issues of his own Flash comic book.
His life began in 31th century, during the era of Legion of Super Heroes. He used to see life as a video game, since he was born with accelerated growth and had to put in virtual simulation, that he feels he live his life as part of video game character. Growing with his cousin, XS (a member of post Zero Hour version of Legion of Super Heroes), he lives most of his tween time in 31th century. Later, he would return to 21th century when he seek help from his uncle, Wally West.
During his tween, Bart was also known as Impulse, a kid who runs very fast with has absolutely no responsibility. With Robin and Superboy, he founded Young Justice (CD Code: 32), the next generation of JLA. Later the membership expanded to include Wonder Girl, Arrowette, and Secret.
During the resurrection of a cyborg Superman in New Titans/Young Justice: Graduation Day (CD Code: 124), Troia and Lilith were killed. Young Justice and New Titans were disbanded. Later, Cyborg founded a new version of Teen Titans (CD Code: 131). He asked former members of Young Justice to join and train together as the new Teen Titans. Thus, Bart Allen joined the group, and later, founding a bit of responsibility, began earning his name as the new Kid Flash.
During Infinite Crisis events (CD Code: 89-90), Superboy of Earth Prime was wreaking havoc in Smallville. Finding there's no other way to stop Superboy, Bart Allen and Wally West bring Superboy to the Speed Force (the element that gives DC speedsters powers). Few days later, Superboy's back from the Speed Force, followed by Bart who's wearing Barry Allen's Flash costume. Bart looks few years older. It seems that both Superboy and Bart has been living in the Speed Force for few years. After the crisis, the Speed Force was gone, and Bart's losing his speed.
One year later, Bart found out that the Speed Force was actually lives within him. During his Flash comic series, Bart found a way to bring back his super speed. He dons the Flash costume, trying to lives up the Flash tradition. He also fought with his clone, Inertia and his Rogues Gallery (comprised of: Heatwave, Captain Cold, Trickster, Pied Piper, Mirror Master, Abra Kadabra, and Weather Wizard), and finally found his own death at the hands of Flash's most dangerous enemies.
The repercusion of Flash's death can be seen in the ongoing series of DC Countdown, a weekly event that countdowns to something (I don't know). Wally West, along with his family, has also came back from the Speed Force, with the help of Legion of Super Heroes (pre Crisis of Infinite Earths version) in crossover JLA and JSA comic books.
CD Code: 286