S2·E20 The Soldier of Loneliness, Burai

Mega Man is pulled into the portal to Mu, and is followed by Hollow, Lyra Note, as well as Yeti Blizzard and Dark Phantom, Vega, and Copper. Hollow finally overwhelms Geo and pulls the Sword of Zerker out of Omega-Xis and presents it to Vega, who has by now convinced Dark Phantom and Yeti Blizzard to help her in exchange for immortality. Geo is joined by Sonia and the two discover and awaken a comatose Solo (Rogue's human identity), who weakly explains how he is the last inhabitant of Mu and protects the seal on Le Mu. Though greatly weakened, he transforms into his wave form and goes off to confront Vega.