There will be a lot of chaos happening at the beginning of the battle, including plenty of officers close to your starting point, as well as some that even defect to the enemy's side. Once it's all clear, get into the water and start swimming towards Fan Castle itself. Watch out for the boulders while fighting outside and defeat all of the officers there to finally secure the place.
Lu Meng and Wu should now appear as help for you, but they will get ambushed by Shu and some ballistas. Your goal is to take out the officer in charge of them, so take the eastern exit out of Fan Castle and start heading in that direction. Once Zhou Cang is dead, Wu will continue moving and then get ambushed by Guan Suo and Wei Yan inside the garrison.
To get inside this garrison, you'll need to go south and around to jump down into it. It is also around this time that Guan Xing will have appeared close to the central area of the map, and he'll begin dropping rocks. He must be defeated in order to stop the falling rocks. Pang De is also isolated in the northwest and needs to be rescued, so head over there when you get a chance.
Go onto the west side of the map and begin moving southward, only to be stopped by the gates being shut down. Wu will bring in some rams to break down the gates, so you'll need to wait until they have broken through one of them. When they do, go and start clearing out the area of enemies. Eventually, Guan Yu's children will show up, including Guan Suo, Guan Ping and Guan Xing.
Take them out and then go to the gate leading to where Guan Yu is located, only to find it closed. It's guarded by Guan Yinping, so defeat her to make it open. Guan Yu has quite a bit of health when compared to the other officers in the stage, as well as more strength. One you take him out, then the battle will be over and you'll have finished the Historical battles for Wei.
|You need to rescue Pang De before he retreats, which will extend the final movie a bit. He is located near the floodgates and is fighting with two enemy officers. After clearing the castle of all enemies, exit it into the central area. From here, go all the way west and into the area leading up to the floodgates, where you see Pang De with the two enemy officers. Defeat both to rescue him and get this star.|