Western Slingshot Woods

Strategy 1 (Not Recommended)
Warning: Remember to use The Blues in Tricksters and not Rogues to dispel Adventurer. Otherwise he will counter you and dealing double damage.

Choose Matilda in Druid, Bomb in Pirate and The Blues in Tricksters. First, always attack with The Blues to dispel. Then heal with Matilda if the birds' health are full and if not, attack with her. Then, attack with Bomb. Repeat this over until you win or lose.

Strategy 2 (Recommended)
By: Iamarepeater

I recommend you come here when you have the Princess class for Matilda.

Choose the following birds and classes:
 * Red as Paladin
 * Matilda as Princess
 * Jay, Jake, and Jim as Trickster/Bomb as Capt'n

Now follow the steps below:
 * 1) Attack with all birds.
 * 2) When Adventurer uses Counter, attack with Trickster/Capt'n first.
 * 3) Heal the attacked ally with Princess.
 * 4) Repeat until you win.

In Summary
Adventurer Pig can dispel helpful effects, resist harmful effects, and counter for 200% damage of normal. You'll need the right Classes and Equipment to take him down.