How To Get Zhou Yu´s Level 4 Weapon:
This one is really easy; I actually got it on accident. Start playing the
stage " The Battle of the Wu Territory" on Sun Ce´s side, and make sure that
the difficulty is set on Hard or Chaos Mode. Now, all you have to do is take
over both of the enemy forts. ( Not the one at the bottom, where Taishi Ci is,
the other two). To do this, you must kill both Yan Baihu and Wang Lang. After
that is done, you should get a valuable item report in the last fort. The box
can be found on top of the western wall.