Eh I've played that boss it's basically ghosts of mavericks like Vile Sigma etc. attacking Zero, I'm still not sure about Sigma actually appearing in the actual game and you have to fight him or something. But I guess if Capcom doesn't want to be original go ahead and put Sigma in, I perosnally got kind of pissed around when X6 came out because you would think that they would stop using Sigma for at least once, but nah he always just comes on at the end and you fight him....kind of gets annoying after 10 years.