For those who have not completed the game, this page may contain spoilers regarding the plot. Discretion is advised.
In Xenoblade Chronicles, Battle Arts can be levelled up. Initially, they can be increased to level 4. To unlock up to level 7, an intermediate book is required. To unlock up to level 10, an advanced book is required. Intermediate books can be bought from vendors. Advanced books are found in gold chests, which may be dropped by level monsters above level 45.
All physical and Ether attacking arts at level 1 have an additional hit rate of 5%. Each level increased will increase the hit rate further by 5%. However, the hit rate will not increase beyond 25% at level 5 or higher.
Furthermore, arts will have their effects enhanced by levelling up. These enhancements may include, but not limited to: increased aggro added to enemies, increased damage, increased healing power, increased buff or debuff duration, and reduced cooldown time.
Drop Rates of Advanced Books Edit
Generally, the drop rate for the advanced books are extremely low — some have a drop rate of less than 1%. Higher level monsters tend to have higher drop rates. The save and reload method can be used to keep opening the gold chest until a desired advanced book is obtained. Up to two of four named books can be acquired without duplicates (e.g. a given monster can drop up to two of either Back Slash, Battle Soul, Slit Edge or Light Heal).
|Slit Edge||Ether Light (Colony 9)|
|Back Slash||Ether Light (Colony 9)|
|Light Heal||Ether Light (Colony 9)|
|Shaker Edge||Kyn Shopping Street (Frontier Village)|
|Air Slash||Refugee Camp (Bionis' Leg)||
|Shadow Eye||Refugee Camp (Bionis' Leg)|
|Battle Soul||Kyn Shopping Street (Frontier Village)||
|Stream Edge||Refugee Camp (Bionis' Leg)|