you have to build a strategy depending on your heroes. And the characteristics of your character
My usually skill for Bs = Sacrifice(very good aoe skill with ignore def for atack all party enemy).. next Skill shining Wall (Very good aoe heal for all party+not little dd back to enemy)...Then i use Star Curse single atack(for use this skill need alot m.atack) maybe use Light Shok(i not use because i have little HP but very more atack)
Last my Skill is Heal single...(because when be next round you not be have +def atack from Holly throne skill)
WB= sacriface(+your party be doing more dd)>; 2 skill star curse>; ;3 skill bane curse>; 4 skill Spirit Bound
For use this skill u must have beast Chimera.
But better use your stratege:That will fit your style of play .