Abyss Walker Class Mastery I

[RWalker]

It says that it increases the strength and agility by 30% but it only increase the Atk by 10%

[NearLawlet]

Actually, 30% STR and AGI are applied to your town stats the moment you learn Class Mastery 1;

But you can get an additional 10% attack power when you use Illusion Strike/Shadow Focus.