[This content is for mid/late-game players, like who wants to craft Homunculus or Reappraisal stones.]
This Beast has a horrible passive: he applies “Electric Shock” (the damage you receive will increase under the Electric Shock Effect. The recovery amount you receive will be decreased by 50% and you’ll be inflicted with Continuous Damage proportionate to 10% of your MAX HP every turn. You must reach 100% HP in order to remove this effect).
FRONT LINE:
That’s why you should bring at least 2 healers here: Colleen/Hwahee (that heals and grants attack buff) and a second healer like Belladeon (or Louise if you got):
BACK LINE:
In the back line you should put 4 fire damage dealers like Trevor, Laika, Shihwa (all recommended in vampire) and Brandia if you have. An other very very very good unit for Wind Beast is Perna, she is an awesome damage dealer and helps a lot with heals.
Good luck !!
Summoners War - Tips 