How do I fix it? There’s no vsync option so I’m just stuck with it?

I'd tell all my friends to check this game out, but I don't have any friends.

Maybe I missed something in the tutorial, but.. how do you reliably dig down? Digging is a pretty important mechanic, and it's pretty easy to dig left and right (move or aim that way), and dig up (up on left stick), but digging down seems to be really awkward. I've tried hitting down on left stick. I've tried hitting down on right stick. I've tried down on d-pad, just in case. I've tried standing still, jumping, and falling before hitting it. I expect I'm missing something, but I really shouldn't be able...

Where can he be found?

I beat the entire game on default difficulty in my first session. This means it is too easy lol. One of the better roguelikes ive played though. Loved it. Is there more content on higher difficulties, cause I did unlock a new one.