This is mission 12, the final mission of the Green Path, in the Path of War of Stronghold 2.
The King's shelter is found by the three lords. As he is out of assistance and time, Barclay decides to siege his final stand and take the crown. But two other competitors, the Hawk and Steele also joins up to the final fight. The crown will be the lord's whose troops deal the killing blow on the King.
The King is encamped in a moderately fortified stronghold. It has multiple defense lines with full of traps and pitch ditches. You get a very small army at your disposal and most of your men will be dead when you reach the King. Barclay attacks in the east and Pascal in the southeast. You start on a small island in the west.
Regroup your army on the island. Send your eight burning carts to the wall section with the rolling logs to trigger them. They all will be shot down by arrows, but they accomplished this minor task. Send all your troops on the top of the slope a bit further. Instruct your remaining catapults to create a breach in the wall next to you. Send archers to the fore to trigger man traps. Don't let the enemy archers light pitch ditches or else you lose valuable time.
March your troops forward, but let the "friendly" troops move first, springing traps, lighting up pitch ditches and creating holes in the walls on the way. Stay close to them and when the last walls are breached, march to that position. Let the allied knights trigger killing pits and pitch ditches, and when they are all done, rush in with all your troops. Set all your troops on aggressive and head directly for the King. Repeatedly click on him if your soldiers engage the guards at the campfire. Your troops should be an inch forward to Barclay's and Pascal's troops. It's a pure matter of luck to win the mission, but you can maximize your chances by taking the lead in the very last moment.
Steele wins the race and owns the crown. Barclay and the Hawk swears fealty to the new king of England.