Xuanhuan: At Death's Door, the System Lets Me Burn Through My Lifespan Without Limit

[Certified as the web's most popular online novel by author Xie Hui]

"Spend one year and three months of lifespan to learn Iron Shirt."

"Spend three years and six months of lifespan to reach minor mastery in Tai Chi."

"Spend twenty-two years and nine months of lifespan to perfect the Muscle-Tendon Change Classic."

When Li Long mastered Iron Shirt in an instant, the veteran bodyguard who had studied it for thirty years burst into tears.

When Li Long perfected the Muscle-Tendon Change Classic in an instant, the master who taught him nearly stopped breathing.

Li Long was helpless too. It wasn't that he wanted to improve; if he didn't, he'd die!