The End of the World: Cut Green Tea with Your Own Hands and Get a Reward of One Billion

[System] + [Space Power] + [Hoarding Materials] + [Decisive Killing] + [Not the Holy Mother] + [Profit First] Lin Xuan was reborn the day before the apocalypse broke out, and the first thing he did was kill his green tea girlfriend. "Ding! It is detected that the host has strong hatred, and the doomsday domination system is activated!" "Mission 1: Revenge, kill Xu Lina, reward 1 billion RMB!" "Task 2: Suffer the anger and kill the green turtle, and the reward will be sudden death on the spot!" Just kidding, do you still have to choose? I am worried about having no money to spend! In my previous life, I lived a humble life and died miserably, worse than a rat in the gutter! In this life, I will stock up on supplies, kill zombies, explode crystal cores, and climb to the top step by step to become the strongest! Save humanity? No time! As long as I live a cool life, that's enough!