Play the battle of Guan Du.

Choose 2 characters with Lady Luck.(2 lvl 50 and both from the same forces are recommended.)

Choose 2 horses. Both with Find Saddle.

Start. Head west and jump down the cliff. There will be a box.

Head to xin pi and kill him. If he drops a horse take it.

Go to the river and head west. You will find Cui Yan nearby. Go to him and Zhen Ji will appear. Kill the both of them.

Now head north west and then jump down. Kill chenyu qiong and also kill the rest in the main camp. Dont kill Yuan Shao first.

With full musou and on the horse, you can kill Yuan Shao with a lvl 50 character.( I tried with Guan Ping)