@beardalaxy I did not know there was such a thing. I just took the old video from Nico Watch. This isn't 4k, it's 1536 as 6x took forever.
I saw your video, that's why I tried it.
I used realesrgan which can nuke some details (which you can see on the fire), but out of all the upscalers it seems to make the most clear and defined image, which is great for bad apples since it's just silhouettes.
I also got the latest Flowframes from Patreon and used RIFE.