Here is the full list of all 31 Scarecrows of Illyria achievements.
Survived Act I.
Survived Act II.
Survived Act III.
Survived Act IV.
Survived Act V.
Flirt with everyone on the island.
Didn't dance with anyone.
Danced with the same person at the Unity Harvest Festival *and* Last Night.
Found out who or what is possessing an islander before Act 4.
Helped Mitch get elected.
Helped Polly become a pirate. Sort of.
Helped Lanja reconcile with her new friend.
Helped reinstate the Mages as the governing power on the island.
Helped reinstate the Knights as the governing power on the island.
Helped stablize Carther's magic.
Helped Kate find a new vocation.
Helped Wes with his family life.
Helped Arken find inner peace.
Helped Thompson learn how to better communicate his needs.
Discovered Abhorsen and Ceilidh's shared history.
Helped Abhorsen gain confidence in himself.
Nab two flirt points with two different people all from one dialogue choice.
Didn't dance with anyone at Last Night.
Didn't chose to date anyone.