At the beginning of the battle, go south down either of the three paths. Your first goal is to get to the base in the southeast, where Yuan Shu is located, and clear a route to get the supplies to Sun Jian. There will be a few officers along the way, with two near Yuan Shu and one near Sun Jian. Along the way to Sun Jian, Hua Xiong appears from the south, so make sure you defeat him, although he is slightly stronger than the other officers so far.
Start making your way along the path heading to the west, where you'll trigger a trap of arrows from the nearby base. When you see some stairs, go up them and then jump into the base, defeating the officer to stop the arrows. As soon as you enter the next base Zhang Liao will appear. After defeating him, you will see some ballistas on the hill to the east. Try your best to quickly destroy them and then the gatekeeper to open the gate.
Kill the officer inside to take control of the base, and then the next officer to capture the catapult. Use this catapult to destroy the two enemy ones on either side of Hulao Gate. Doing this will open the gate, as well as make Lu Bu spawn in front of it (you can't hit him with the catapult). You won't be able to do much to Lu Bu, so ignore him and continue on with the battle.
On your way north up the west side of the map, you'll encounter Diao Chan. If you defeat her, then Lu Bu will mercilessly hunt you down, so it's best to avoid her as well. Defeat the officer by the gate to open up the path leading up to Dong Zhuo, but not before he sets fire to it. Take out the officer guarding the last gate, then defeat Dong Zhuo to put an end to the battle.
