Blessing scrolls can be bought from the Item Mall, from lv 85 and 90 metins also from 2 or 3 quests.
Althougth they do not increase the success chance of an item,
the item will NOT disappear if its upgrade fails: it will downgrade.

You can use this item by dragging it to the desired gear item. The price you need to pay will be the normal Blacksmith's price. You will need to have the upgrading materials in your inventory.

EX: I try to upgrade a +8 weapon to +9. It fails. My weapon is now +7.