Mastery Bonus Options have 2 types:
In Set items: Damage Decrease (200-300-500)
In Weapons: Increase all stats (500-700-1000)
You obtain Mysterious stone from exchange Jewel of Excel at NPC "Moss" in Loreancia.
You can obtain Mastery option from:
- Chaos combination
- Mysterious stone
When upgrading ruud set and weapon, you have a chance that Mastery option will disappear.
1. After using mysterious stones all excelent options in set items disappear
2. After upgrading set or weapon from BA->DA excelent, mastery options disappear