The Weakest Hunter? Then I'll Upgrade Alone

Many years ago, cracks appeared in the world. These cracks connected other dimensions and were called "doors". There are various monsters in the door, and people have awakened different abilities to fight against the monsters, and are called "hunters". Jiang Wenming, the weakest E-level hunter, encountered a terrible hidden challenge during a team mission. At the moment of life and death, he actually got an upgrade system! With the use of the system, can he become the strongest hunter? This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.