Villains Want Mercy

Sometimes when defeated by the hero, the villain goes down gracefully. Sometimes he realizes he's doomed and demands you stop fooling around. Sometimes he tries to take the heroes with him. Sometimes the villain is so badass he just won't stop fighting until he's Deader Than Dead. This trope is not about those villains.

Smug Snakes, Dirty Cowards, and bad guys who suffer from Villain Decay rarely go down with their heads held high. For all the bravado and confidence they usually project, they're much more likely to get on their hands and knees and beg for mercy. This also serves to contrast them with the hero, as heroes usually don't beg for mercy from the villain in the opposite situation, at least not for themselves. Very rarely, it's the act of a Noble Demon who is consistent about offering his foes mercy, and expects the favor to be returned. Depending on where the hero is on the Sliding Scale of Idealism vs. Cynicism, they might call the villain out on how many people they've denied mercy before sparing them anyway. Others may deliver a "Reason You Suck" Speech and leave the villain alive just to spite him. Or they might just scoff at this and shoot him.

If the hero does grant them mercy, they may perform a Heel–Face Turn out of gratitude. However, it's very common for the villain to attempt to attack the hero one last time, usually while their back is turned. This will rarely work.