If you want to see the of that Haki, continue into Episode 462 .

If you are skipping through episodes or just want to relive that legendary moment, here is the exact answer. Luffy uses Conqueror’s Haki for the first time at Marineford in Episode 461 .

It remains one of the most iconic "power-up" reveals in anime history—not because Luffy trained for it, but because his will to save his brother was so strong that the universe itself bent to his command. Did you miss this moment when you first watched it? Let me know in the comments below!