I was surprised to see the Sephiroth challenge before he was actually to be released in Super Smash Bros. Ultimate. All the other DLC characters came to your roster automatically, but you could get him early if you could beat him.
I didn’t know how many tries I had to beat him, so I chose my best character at normal difficulty.
He gave me a little challenge, but I was able to beat him on my first try with Palutena.
I hope they do this type of challenge for the future characters on DLC.