This is clearly a bad Waifu2x upscale, but I've never seen the original and I've had no luck searching for it, so I have no idea what the full size of that is or what it really looks like. If anyone has that, regardless of size or quality, please post it.
Assuming this is the best there is, I'd like to see if someone can fix the many errors in this image, the worst being the hands on Aqua, Yunyun and Megumin (but even Darkness' have issues). Most of the rest is just lots of shoddy linework (too thin or thick, wavy etc.) though, which I circled here:
https://files.catbox.moe/vwgsrv.pngYou can also add other fixes as you see fit, I'm sure I missed some.
