For damage from behind (DFB):
* By default, DFB deals 55% more damage (初始状态从背后射飞镖伤害提升55%)
* With 12% Shadow Strike, DFB deals 72% more damage (学习背后增伤的技能后,背后射飞镖伤害提高72%)
* With 16% DFB Weapon, DFB deals 94% more damage (再配上16%背后增伤的武器,背后射飞镖伤害提高到94%)
* (these attributes seems multiply to each other other than add up)