Great Cliffs - 4

Enemies
If Howler manages to unleash his Ghastly Cry skill, any of these pigs can be summoned:

Strategy
Choose Matilda in Druid, Bomb in Cannoneer and The Blues in Rogues. Heal with Matilda if the birds' healths are not full and if they're full, attack with her. Then attack with Bomb and The Blues (After Howler calls for help, weaken the other pigs every turn until they are almost dead. Then, it will be easier to knock out them). Use the Rage Chili immediately on The Blues when it is full for the first time and on Bomb to destroy all ghosts at once when it is full for the second time. Repeat this over until you win or either lose.

In Summary
Howler can summon Ghosts to help him in the battle, and his main attack can poison the birds to deal big damage.

Trivia

 * You can only get 3 stars if you defeat the Howler before he calls the ghosts.
 * In version 1.0.0, Howler was called {pig_ghost_banshee_boss_name}.