Ichioku-nen Button o Renda Shita Ore wa, Kizuitara Saikyou ni Natteita follows Allen, a "failed swordsman" who achieves god-like power after training for a billion years in a frozen dimension. Around Chapter 18, the manga focuses on Allen's continued shock of his academy peers with his immense power while unraveling the mystery behind his suppressed inner power, Zeon. For more details, visit Fandom .