One-Punch Man

One Punch Man (ワンパンマン WanPan-Man) is a Japanese webcomic and manga series created by ONE. The webcomic started in July 2009, with more than 10 million total views and 20,000 a day. Sheuisha's Young Jump Next picked up the series, had Yusuke Murata, known for Eyeshield 21, draw the series with the same writer, ONE.

Plot
Follows the life of an average hero who manages to win all of his battles with just one punch! This ends up being the cause of a lot of frustration as he no longer feels the thrill and adrenaline of fighting a tough battle. Maybe all of the hard training to become strong wasn't worth it. After all what's so good about having an overwhelming power?