All characters:
At the title screen, press Square(2), L1, L2, R1, R2, Square(2) to unlock all nineteen hidden generals.

All Shu Generals:
At the title screen, press Square, R1(5), R2(2) to unlock all Shu Generals.

Edit mode:
Successfully complete musou mode with all characters except Dong Zhuo, Diao Chan, Lu Bu, Yuan Shao, and Zhang Jiao to unlock edit mode in the options menu. Alternately, press L1, L2, R2, R1, L1, L2, R2, R1 at the title screen.

BGM Test Option:
At the title screen, press R1(2), R2(2), L1(2), L2(2) to unlock the BGM test selection in the options menu.

Alternate introduction sequence:
Successfully complete musou mode with any character.

Unlock Huang Zhong, Ma Chao, and Jiang Wei:
Successfully complete musou mode with Zhang Fei, Zhao Yun, or Guan Yu.

Unlock Xiahou Yuan and Zhang Liao:
Successfully complete musou mode with Xiahou Dun, Dian Wei, or Xu Zhu.

Unlock Taishi Ci, Lu Meng, and Gan Ning:
Successfully complete musou mode with Zhou Yu, Lu Xun, or Sun Shang Xiang.

Unlock Zhuge Liang:
Successfully complete musou mode with Zhang Fei, Zhao Yun, and Guan Yu.

Unlock Liu Bei:
Successfully complete musou mode with Zhang Fei, Zhao Yun, Guan Yu, Huang Zhong, Ma Chao, Jiang Wei, and Zhuge Liang.

Unlock Sima Yi:
Successfully complete musou mode with Xiahou Dun, Dian Wei, and Xu Zhu.

Unlock Cao Cao:
Successfully complete musou mode with Xiahou Dun, Dian Wei, Xu Zhu, Xiahou Yuan, Zhang Liao, and Sima Yi.

Unlock Sun Jian and Sun Quan:
Successfully complete musou mode with Zhou Yu, Lu Xun, Sun Shang Xiang, Taishi Ci, Lu Meng, and Gan Ning.

Unlock Lu Bu in free mode:
Successfully complete Stage 2 (Hulao Gate) in musou mode with at least 1,000 KOs.

Unlock Diao Chan, Dong Zhuo, Yuan Chao, and Zhang Jiao in free mode:
Successfully complete musou mode with at least one member of each kingdom.

Unlock Side Selection in free mode and BGM test option:
Successfully complete musou mode with at least one member of each kingdom.