I Understand the Laws of Time by Killing

[Fantasy + golden finger + single female protagonist + the protagonist gradually grows + decisive killing + fast pace + not brainless + no blood] In this fantasy continent, the protagonist is selected by the Pocket Watch of Time, and his life trajectory has changed since then... "What got sucked into it?" "It turns out to be my golden finger" "As long as I kill enough, I can improve my cultivation and realize the perfection of the law of time!"