Is this 64 x 64? Because it seems that there is a tiny bit of the blue "slime" visible to the right of the snails' tails that is too small to be a full 1 pixel of the 64 across (pointed to in red)? Otherwise, it seems the sprites have been kept at the correct resolution.
I didn't know that Unity does not properly support 64x64 resolution on WebGL. So in pc build, you will see proper 64x64px resolution but for some reason, WebGL is rendering in 640x640. I know how to resolve this issue today, but 20minutes before the submission end I didn't even know that this was happening ;/
