The brave tree is all about combat, increasing the power of certain attack and allowing more time for others to help prevent you from being overwhelmed. (twinfinite.net)
Each boss has various limbs that, if damaged enough, can be cut off which can cause it to deal less damage or straight up stops it from doing certain attacks. (monstervine.com)
Most importantly it will actually give you frame data, which lets you know if certain attacks are safe or not. (darkstation.com)