Begin immortality by slaying demons

Spend life energy to infuse martial arts, and you can perform unlimited deductions.
Shen Yi's mortal body only has a lifespan of less than a hundred years. Fortunately, he can gain his remaining lifespan by killing demons.
In the troubled times where evil spirits are everywhere, the long sword is revealed, causing the liver and gallbladder of these creatures who have lived for thousands of years to burst!
From [Eagle Claw Technique] to [Eight Desolations Splitting Heavenly Hands], from [Demon Subduing Fist] to [Golden Body Prison Suppressing Dharma Appearance]!
Shen Yi would occasionally ponder, how come this life span increases with time?
He put the sword into its sheath, raised his eyes to the sky, and heard that there was a Jade Palace above the clouds. It was filled with thousands of saints, each of whom had experienced endless years.
This time I came to heaven just to borrow a million years from the immortals to prove my path to immortality.
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This book is also called "You are asked to use your life to practice martial arts, but you are going to use someone else's?" ", "Fellow Taoist, please stay, your longevity is destined to be with me."