I used waifu2x, a free, web-based upscaler that uses deep convolution neural networks, and I've gotten some incredible results out of it for certain textures, most notably the goo textures. I manually ran each texture through waifu2x, and inspected them, testing settings to see what looked best. I used Bighead's Custom Texture Powershell script to make the goo and other seamless textures, big thanks to him! A few original textures are too low-res for waifu2x to make good upscales from. Using Gimp, I manually upscaled a few textures: low-res banners, letters, text, and small character maps. I also manually retextured certain textures that I felt required more than just upscaling to be acceptable in a UHD pack. Most notably the main menu A, B, and C save blocks were retextured. For the wanted poster, I edited a screenshot from an in-game cut-scene that shows the poster at a higher resolution.