Here is the full list of all 20 White Pearl achievements.
Completed the Sigil Questline, thereby unlocking access to Ancarna Castle.
Made a decision which would change the fate of the world.
Attended the Harvest festival at Prevesta and be granted access into the item shop.
Chapter 15 completed.
Chapter 14 completed.
Completed the alternate ending.
Chapter 13 completed.
Chapter 12 completed.
Chapter 11 completed.
Chapter 10 completed.
Chapter 9 completed.
Chapter 8 completed.
Chapter 7 completed.
Chapter 6 completed.
Chapter 5 completed.
Chapter 4 completed.
Chapter 3 completed.
Chapter 2 completed.
Chapter 1 completed.