The Price of Reverting to Death Is Doubling the Pain

Traveling to a different world on the verge of destruction, I gained the controllable ability to roll back after death. The price is fatal: for every second added to the return time, my pain will double from the initial value. In order to protect the people around me, I extended the duration of my return time and time again, and walked step by step towards the abyss of pain. Can I still complete this doomsday redemption before my sanity collapses?