Board Thread:Questions and Answers/@comment-70.62.125.212-20150128154605/@comment-101.168.255.245-20150221135524

You should check how your team is set up and when their BB's are set to activate. Some units will only use their BB's when an enemy has less than 50% hit points, some will use theirs randomly and others will use it when enemies have over 50% hit points.

The position you have your unit in your team is important as well - units that only use their BB when an opponent have over 50% health left should be put first in order and so on so they are more likely to have healthier enemies left. The opposite applies for units who only attack weak enemies,  The order from first to last under the Manage Squad is Top Left first, then Top Right, Middle, Bottom Right and Bottom Left - think of the order as being like how you would write out the digit 3 from start to finish.

You can check what type of BB type your unit is by going to the below link. For example, look up Kuda and you will see just under his stats that he only uses his BB in arena when his opponent has less than 50% health remaining. Healing units (Tia, Themis, Tree, etc) will check your teammates health before deciding whether to heal - eg. your units might need to have less than 25% HP remaining before they use their heals - so if you have a team with 26% health left you are not going to get healed! hope this helps.

http://touchandswipe.github.io/bravefrontier/skillseffectsguideglobal?