It's been awhile since I've read a manga that has such a great blend of humor and action as One-Punch Man.
The original series began as a webcomic in 2009 by a man mysteriously known as One. The remake is illustrated by Yusuke Murata and written by the same One. That is the version I've been following.
One-Punch Man is an action packed manga, full of bizarre villains and heroes. The main protagonist is a man named Saitama, who is as unremarkable as they come. He has an average look, build and even a laid back disposition. What makes Saitama unique is his strength and love for mankind... especially his home town Z-City.
Ever since Saitama was a child he wanted to be a super hero. After numerous encounters with criminals he finally decided to take action and train his body to perfection. Through basic calisthenics (push-ups, sit-ups and running) for three consecutive months, Saitama was able achieve incredible power. He acquired enough raw strength to destroy almost every enemy he faced with one punch.
In his world the cities are given names from the alphabet (City A, B, C, ect....Z) and are often attacked by monsters. These monsters are called "Mysterious Beings," and range from normal humans to hybrid (beast) humans to intergalactic conquerors. Each attack against an alphabet city by one of these is given a threat level. Those levels range from "Wolf" which is a human level threat, to "God" which is an extinction level event. No one knows where the Mysterious Beings come from but they all seem to have an instinctive hatred for humans.
To handle threats against mankind a group of powerful individuals began the Heroes Association. This association employs citizens as heroes and provided them pay and services for protecting the alphabet cities. The hero classes range from "C" (ordinary human) to "S" (superhuman) and all officially recognized heroes are part of the Heroes Association.
Saitama joins the as the lowest ranked C-Class hero and works his way up through the ranking. Along the way he gains a disciple named Genos (The Demon Cyborg) who is impressed by his strength. Genos is on his own quest for vengeance and tries to learn the secret of Saitama' power. Ironically Genos is given the ranking of S-Class based off some of the monsters Saitama defeated. He is also one of the few individuals in the Heroes Association who knows how strong Saitama really is.
The manga was recently turned into a 12 episode anime that ended in December 2015. The anime was taken directly from canon material and featured superb artwork and battle scenes. The great thing about this series is that it's a parody of the whole super hero genre. In the video below Saitama shows up to stop a meteor from destroying all life on Earth. Check out the anime and check out the manga....if you like what you see. Don't forget to purchase official copies from the Mangaka, cuz those guys work long hours for little pay or appreciation.