the last guy in the first campaign in Magic the gathering; dual of the plane walkers. the guy with blue and black creatures.
I where about to get owned, then he used the artifact creature Angel of Retribution (or something like that) that have a feature so that if you have this creature on the battlegrounds, you can't lose.
I, to my luck had played with the blue deck and i had a card that allowed me to take full control of another players creature.
So i took his card, and he couldn't kill it since i never defended, and the destroy creature cards doesn't work on artifact creatures. But he kept wailing on me with uber-boosted creatures with life-link (a ability that transfers all the damage they deal to HP for the player controlling the creature).
So i took beating after beating, he gain more and more life. This went on for over 45 minutes, until I had -1247 HP and he had a shitload of life, but i won!
That's because of a rule in Magic, If you have drawn all the card in your library, you have to win that round or lose the game. this is to prevent an eternal stand of where booth players have no cards to use and no more cards in their library.
In total the boss battle lasted for 83 minutes.