Broadcasted Death Game in a Dungeon! BDGiaD

Mike was once a martial arts genius. He was gifted both in body and in comprehension. He was on a one-way track to being the next big martial artists who'd dominate any competition he joined, earning the prize money without even trying. But one freak accident...and that one-way track became blocked in such a way that it was impossible to advance.

Having no other talents, Mike was forced to focus on his studies and take up a regular job as a regular office worker. Which he did. But his life had lost the meaning it once had. The wonder martial arts and fighting had brought to him was gone.

But one day, as he was walking to work, the world went white and he found himself in a forest on his own. A screen popped up to him and explained what sort of situation he was in.

He was in some sort of death game that was being broadcasted throughout the known multiverse. Good news, however, was that he was healed. He could fight. He would fight.

Given mysterious abilities and a weapon, Mike has to fight his way through a dungeon, each level different than the other. But he doesn't mind: A battle junkie like him was only good for stuff like this anyways!