The tournament and the duel
On screen the tournament is a festive moment, far from its role as training for war. It's a classic of medievalist film when it doesn't constitute its very substance, as in the film A Knight's Tale (Brian Helgeland 2001). The tournament depicted is always the joust of the late Middle Ages.
The duel contributes to the heroisation of characters by giving rise to individual feats. It also serves to emphasise the bravery and nobility of spirit of the warrior leader. In Monty Python and the Holy Grail Arthur fights the Black Knight, methodically severing his limbs. The fight between Mordred and Arthur in Excalibur by J. Boorman (1981) is more dramatic.
The Last Duel (2021) by Ridley Scott depicts a real judicial duel that took place in 1386. Jean de Carrouges and Jacques Le Gris fight to the death over an accusation of rape against Carrouges' wife, Marguerite de Thibouville.