Have a saved game file from Samurai Warriors: Xtreme Legends to unlock Inahime.
Have a saved game file from Samurai Warriors to unlock Maeda Keiji.
Successfully complete the game on the normal difficulty setting to unlock the hard difficulty setting.
Successfully complete the game on the hard difficulty setting to unlock the expert difficulty setting.
Successfully complete the game, then start a second game to begin with all magic skills, troop levels, and the weapons, helmets, and armor that were equipped at the end of the last chapter. Unlock all battles to start a new game with weapon and armor bonuses. Unlock all moves to start a new game with extra troop types. Unlock all officer biographies to start a new game with a troop level and experience bonus. Unlock all music to start a new game with a gold bonus.
Using the Rampage can provide many rewards, additional gold, experience, etc., increase your Samurai's Officer Skill levels, and increase their attributes WAR (Attack) , INT (Magic Skill offense and defense), and STA (Defense). If you enter a Rampage with an opposition Samurai, you may notice a "bonus" above the opposing Samurai after you achieve 100 defeats, which then released the enemy officer into the game. This may be "War Cry up" or "INT up". If the enemy Samurai has a greater amount in any attribute or skill, you will have an opportunity to increase your own based on their amount, should you defeat them in the Rampage. The greater amount they have of "War Cry" or "Freeze" in comparison to your officer results in the more you can potentially gain at the end of the Rampage. However, for the three main attributes, the game uses the following rule. If the difference is between 1 to 10 you will gain an increase of 1 for that particular attribute. If it is 11 to 20 you will gain an increase of 2. If it's 20 or more you will gain an increase of 4. Therefore, try to choose your Rampages wisely noting the attribute difference. Hopefully it will not be not too great or it will be very difficult to win. The large benefit of the attribute differences is pre-mission; you can view all visible officers attributes before you start the battle. Here you can elect who you will Mass Rampage. Then, simply manipulate your attributes by changing your helmet, weapon, etc. to deliberately drop one of your attributes, in order to increase it by Mass Rampaging.