The battle at the Mummer's Ford was a battle fought between the forces of House Lannister, under the command of Ser Gregor Clegane, and the forces of House Stark, under the command of Lord Beric Dondarrion. It ended with a decisive Lannister victory.
Before the Battle[]
Lady Catelyn Stark has taken Tyrion Lannister prisoner and has taken him to the Eyrie to be held prisoner by her sister, Lady Lysa Arryn. In retaliation, Lord Tywin Lannister has sent Gregor Celgane to ride through The Riverlands and burn villages. Lord Hoster Tully has dispatched Ser Marq Piper, Ser Karyl Vance and Ser Raymun Darry to King's Landing, begging King Robert Baratheon for both assistance and justice.
The three nobles are instead heard by the King's Hand, Lord Eddard Stark, who agrees to send out a party to bring Gregor t justice. He passes over Ser Loras Tyrell as leader of the party, instead sending Beric. Tywin was trying to draw Eddard out so he could take him hostage and exchange him for Tyrion.
A number of nobles and knights are sent with Beric, including Thoros of Myr, Lord Lothar Mallery and Ser Gladden Wylde. Ser Raymun, Ser Marq and Ser Karyl all accompany them, but Marq and Karyl leave the main force to help Ser Edmure Tully in the siege of Riverrun.
The Battle[]
The group is attacked by Lannister forces and they make a fighting retreat, but are then taken from the rear by the main force, under the command of Gregor. Lothar Mallery, Gladden Wylde and Raymun Darry are all killed, whilst Lord Beric takes Gregor's spear and is mortally wounded. His body is pulled out of the ford by Edric Dayne, who then starts to protect his master. Alyn orchestrates a retreat of the surviving soldiers, and Thoros inadvertently revives Beric, refinding his faith in R'hllor.
After the Battle[]
The Brotherhood without Banners is formed from the survivors of the battle and begins to plague the armies of House Lannister. Tywin laments to his brother Ser Kevan Lannister, later about Thoros and Beric attacking his forces.