Indie game storeFree gamesFun gamesHorror games
Game developmentAssetsComics
SalesBundles
Jobs

Righto, the problem might be with the refresh rate of the monitor itself. I tested out with setting down the monitor Hz values, messing around with Nvidia Control Panel settings and here's what I found out:
- G-sync on, V-sync off, Letting the application control the frame rate = 2000-3000+ FPS
- G-sync off, V-sync off, Letting the application control the frame rate = 2000-3000+ FPS
- G-sync off, V-sync on, Letting the application control the frame rate = ~144FPS
- G-sync off, V-sync on, Letting the application control the frame rate, changed monitor Hz down to 60 = ~60FPS

Video card = GTX 1070Ti, CPU = i7-6700k
I'll DM the video to you.

(+1)

Crap - sorry I missed this.  I can't see a DM feature for Itch.io, can you send it to domarius@gmail.com?  I was just reading up on this, and it seems it might behave better in Godot 3.0, but I made this in Godot 2.1 https://github.com/godotengine/godot/issues/9561 If you have the time, it would be interesting to see if your high refresh rate monitor has trouble with other Godot games, like this one https://globalgamejam.org/2018/games/hyperspace-shoujo or this one https://levrault.itch.io/godot-2d-action-adventure-platformer-demo (that last one has some weird controls - left & right to move, space to jump, and F to attack...)