One Piece: My Name Is Escanor, and People Say I'm Weak

Invincible protagonist + makes up for his weaknesses + beats the whole world into submission + becomes the World's Strongest, one man against the entire world Whitebeard, Kaido, Big Mom, and Red-Haired Shanks wore grave expressions before launching their strongest attacks at the man across from them. “Quake!” “Thunder Bagua!” “Elbaph Spear: Ikoku!” “Divine Departure!” “Holy Sword: Escanor.” The four unleashed a tsunami, thunder, shock waves, and the impact of the mightiest Conqueror's Haki. Their attacks obliterated everything in their path. This combined strike by the Four Emperors was enough to make even the World Government tremble with fear, and powerful enough to pulverize an entire island in one blow. But the next second, when that man launched his own attack, a thunderous boom rang out, and their mighty attacks crumbled like eggs thrown against a rock. The four were stunned. A moment later, each of them bore wounds that were nearly fatal. “Monster! Monster! You arrogant monster!” Defeated, the Four Emperors cried out in fear at the victor. “I already told you, weaklings. The moment you challenged me, your defeat was inevitable.” Escanor, his towering figure carrying an axe like a work of art, regarded them with a calm, composed gaze. Today, the World's Strongest Man was born.