sudomod

When retropie is booted up on my gameboy zero the screen text is very fuzzy to the point where it is almost completely unreadable. Was wondering if there was a way to improve this.

Looks ok for a composite screen to me. Any more pics of the post boot ? The resolution of composite screens has a hard time handling the small font. Try AJ Redfearns 3.5' themes for comparison, specifically designed to help with legibility on composite screens.

That said it shouldn't flicker. Ensure your video cable is grounded as its prone to interference.

Flickering could be a low voltage/amperage thing. Had that problem when testing with a 500mA USB charger sans battery. Also it's recommended to ground to a contact on the Pi close to the video output to prevent interference, keep them as short as possible.