This is an incident that occurred during the battle of Mahabharat. Arjun and Karna were finally face to face on the battlefield and a fierce fight was underway. Two of the greatest fighters the world had ever seen, unparalleled in skills and might, were laying it all out. Its said that soldiers from both the armies stopped fighting just to witness these two warriors in an epic battle. Arjun, on his chariot with 4 white horses, and a charioteer like Krishna looked majestic. Karna, the son of sun god himself, glowing like a drop of mist on a bright sunny day, had king Drupad as his charioteer. Both attacked each other with a hailstorm of arrows; thunder rumbled and the ground itself shaking when their arrows clashed with each other.

When Arjun's arrows hit Karna's chariot, it was pushed back by twenty steps by the sheer force of his arrows. However, when Karna's arrows hit Arjun's chariot it slides back by a mere two steps. Oddly enough, Krishna always exclaimed in excitement when Karna was able to do that, showering praises upon him; and didn't uttered a single word of praise for Arjun who was pushing back his opponent much more. Eventually, it started bothering Arjun. Krishna, his mentor, his good friend, was praising his arch nemesis even when he was clearly outperforming Karna. Finally he snapped.
"I have had it enough," Arjun said, frustrated.
"Are you so blind that you cannot even see who is the greater warrior among us? When I am hitting Karna's chariot, it is pushed by 20 steps. Yet when he attacks us, our chariot is being pushed back by a meager 2 steps. And still, you are praising him and not me. What's up with that!"

Krishna smiled. "Arjun! You are no stranger to my true identity. You know who I am, or what I am; an incarnation of Vishnu, overseer of the universe. I, myself, am sitting on this chariot with you. By my command, lord Hanuman himself is sitting on top of your chariot's roof with your flag. Sheshnag, the serpent king, is holding the wheels to the ground. Nobody should have been able to touch us, let alone move us by even a bit, and yet; all of this and Karna is still moving us two steps back by his attacks!"

Stunned, Arjun replied "I get it now," hands folded.
"To believe that my achievements were solely due to the efforts I made; and were mine and mine alone, was arrogant. I finally see why you always considered him as the greatest warrior".