Black Knight (Monty Python)

The Black Knight is a fictional character who appears in a scene of the feature film "Monty Python and the Holy Grail". As his name suggests, he is a knight dressed in black and behaves similarly to the standard character, a black knight. He guards a "bridge" (in reality a short plank of wood) over a small stream—which could have been easily stepped over by King Arthur but, for unknown reasons, he does not. Although supremely skilled in swordplay, the Black Knight suffers from unchecked overconfidence and a staunch refusal ever to give up.
Overview.
In the film, King Arthur (Graham Chapman), accompanied by his trusty squire Patsy (Terry Gilliam), is travelling through a forest when he enters a clearing and observes a fight taking place between a Black Knight (John Cleese) and a Green one (also played by Gilliam) by a bridge over a small stream. As he watches, the Black Knight defeats the Green one by throwing his sword straight through the eye slit of the Green Knight's great helm (during Arthur's battle with the Black Knight, the Green Knight's body can be seen in a ditch beside the area).
Arthur then congratulates the Black Knight and offers him a place at his court at the Round Table, but the Black Knight only stands still, holding his sword vertically, and makes no response until Arthur moves to cross the bridge. The Black Knight moves slightly to block Arthur and declares "None shall pass". King Arthur, in a conciliatory manner, asserts his right to cross, but the Black Knight says Arthur will die. Arthur orders the Black Knight to move but he says, "I move for no man". Reluctantly, King Arthur fights the Black Knight and, after a short battle, the Knight's left arm is severed, which squirts out copious amounts of blood.
Even at this, the Knight refuses to stand aside, insisting "Tis but a scratch" and that he has "had worse", and fights on while holding his sword with his other arm. Next, his right arm is cut off, but the Knight still does not concede. As the Knight is literally disarmed, Arthur assumes the fight is over and kneels to pray. The Black Knight interrupts Arthur's prayer of thanks by kicking him in the side of the head and accusing him of cowardice. When Arthur points out the Black Knight's injuries, the Knight insists, "It's just a flesh wound." In response to the continued kicks and insults, Arthur chops off the Black Knight's right leg. At this point, the Knight still will not admit defeat, saying, "Right, I’ll do you for that", and attempts to ram his body into Arthur's by hopping on his left leg. Arthur is annoyed at the Black Knight's persistence and sarcastically asks the Black Knight if he is going to bleed on him to win. The Black Knight replies by saying "I'm invincible!" to which Arthur retorts "You're a loony." With an air of resignation, Arthur finally cuts off the left leg as well and sheathes his sword. With the Black Knight now reduced to a mere stump of a man, he says, "All right, we'll call it a draw." Arthur then summons Patsy and "rides" away, using coconuts to simulate the sound of a horse galloping, leaving the Black Knight's limbless torso screaming threats at him ("Oh. Oh, I see. Running away, eh? You yellow bastards! Come back here and take what's coming to ya! I'll bite your legs off!").
Behind the scenes.
According to the DVD audio commentary by Cleese, Michael Palin, and Eric Idle, the sequence originated in a story told to Cleese when he was attending an English class during his school days. Two Roman wrestlers were engaged in a particularly intense match and had been fighting for so long that the two combatants were doing little more than leaning into one another. It was only when one wrestler finally tapped out and pulled away from his opponent that he and the crowd realised the other man was, in fact, dead and had effectively won the match posthumously. The moral of the tale, according to Cleese's teacher, was "if you never give up, you can't possibly lose" – a statement that, Cleese reflected, always struck him as being "philosophically unsound". The story would have been a deformed (or misremembered) description of the death of the Greek wrestler Arrichion of Phigalia.
Cleese said that the scene would seem heartless and sadistic except for the fact that the Black Knight shows no pain and just keeps on fighting, or trying to, however badly he is wounded. Also, as the scene progresses and Arthur becomes increasingly annoyed, his dialogue lapses from medieval ("You are indeed brave, Sir Knight, but the fight is mine.") to modern ("Look, you stupid bastard, you've got no arms left!"), and finally to just plain sarcastic ("What are you gonna do, bleed on me?"), while the Black Knight remains just as defiant ("I'm invincible!" he yells with only one leg left, to which Arthur simply replies "You're a loony.").
This scene is one of the best-known of the entire film. A famous line of the scene, "'Tis but a scratch", is similar to a line the character Mercutio speaks in Shakespeare's "Romeo and Juliet", wherein he demurs, saying "Ay, ay, a scratch, a scratch," referring to his mortal wound, and the former has since become an expression used to comment on someone who ignores a fatal flaw or problem. The phrase "'Tis but a flesh wound", following a character entering "with coconut shells tied to his feet" notably appeared in an early episode of "The Goon Show" titled "The Giant Bombardon", broadcast in 1954; the Monty Python group has acknowledged being influenced by the Goons.
Performance difficulty.
The Knight was, in fact, played by two actors: John Cleese is in the Knight's armour until he is down to one leg. The Knight is then played by a real one-legged man, a local by the name of Richard Burton, a blacksmith who lived near the film shoot (not to be confused with Richard Burton, the Welsh actor of the same name), because, according to the DVD commentary, Cleese could not balance well on one leg. After the Knight's remaining leg is cut off, the quadruple-amputee that remains is again Cleese. 
In the musical "Spamalot", the scene with the Black Knight was the most difficult to play on stage, according to Eric Idle. Penn & Teller created the illusion for the musical.