Talk:Strategies, tips and tricks/@comment-114.121.163.136-20140326102216/@comment-5612420-20140401170122

There's a weebly cookierun blog for the kakao version in english. According to that, for S grade treasures the rough chance of upgrade is:

"+1, +2, +3:  Has a 95%-100% chance to upgrade +4: Close to 50% chance to upgrade +5: Close to 40% chance to upgrade +6: Close to 30% chance to upgrade +7, +8: Close to 20% chance to upgrade +9: 10-15% chance to upgrade"