I feel as though Sigma, being that he's from the first Megaman X, would be a bit.. weak, per sé. See, his fight in that game really only consists of two things: Jumping around, and holding up his beam saber briefly to reflect any incoming projectiles, until he moves on into his second phase, which wouldn't be possible here because it requires his giant, seemingly wall-mounted wolf mech. I feel as though there should be atleast a bit more to his moveset than just those two things. I would say that he would more fight like a mix between X and Zero. Partially with his beam saber, partially with ranged projectiles, firing from his hands and that jewel thing on his head, like he could fire electric orbs in Megaman X5, instead of just firing one beam from his head jewel. I'd think it would make him a bit more interesting than just being a grasshopper in battle who occasionally reflects projectiles shot at him. I was thinking that, since he IS the final boss of megaman x, he should be able to use the same weapons as his lackey reploids can, (E.G. Storm Tornado, Chameleon Sting, Shotgun Ice, etc.), or if not that, atleast that he should be able to use the other ranged attacks he used throughout the X series.