The Hero Wishes to Live

The world had been abandoned. I was the only one left, chosen by the world to fight the impending calamity by myself.
Given the strength to survive, I combated the calamity until my magic ran out and my arms were too heavy to swing.
And finally, at the end of it all-

[Congratulations, you have defeated the Calamity and it's armies.]
[You have successfully saved the planet. The Earth itself wishes to reward you.]
[As a reward, as many as three wishes will be granted.]

I was given a chance to live.

"I wish-"