Mecha-Ude: Mechanical Arms season 1 episode 10
Remember, Brother
The true masterminds behind everything that happened appear before Hikaru and Alma and they end up being ARMS' leader Aljis, and his Mecha-Ude, Fist. And underneath Aljis's mask, they discover it's actually Yakumo, who should've died 100 years ago. What are they truly after? The curtain rises on Hikaru and Alma's final battle to determine the fate of all the Mecha-Udes and the Mecha-Ude users!
