Ah, but it's pico 8's palette like I mentioned in the discription.
I thought nes only used 12 colors plus a background. This is a bigger mystery then I thought. O_O
NES Limitations? It's not NES resolution, nor palette, nor NES 16x16 palette regions. Still looks nice, but doesn't really give an NES aesthetic.
Incredibly cute! Love the sprites and design and the pink + green combo is very pleasant n_.n
A late response, but it's up to 25 colors. 13 for the background, 12 for sprites. But you can't place any color anywhere. A post I wrote on the subject: https://pixelation.org/index.php?topic=10784.msg115062#msg115062