I think is interesting that both in vanilla generations and in the shadow gen stories, both sonic and shadow are implied to be way stronger to what they used to be. I am sure sega wanted them to just fight old bosses for the sake of fanservice but the fact that both normal sonic and shadow can defeat bosses that needed outside help and/or their Super forms before is kinda crazy when I stop to think about it. The rematches of Perfect Chaos or Metal Overlord are insane in concept to me.