Better stock up on Enhancement scrolls.

It's like this in KMS as well.

http://orangemushroom.wordpress.com/2013...#more-5514

There’s also Oko’s shop, where you can spend the Yggdrasil Runes that the bosses drop. He sells Sealed Boxes which contain equipment level 100 and above. What’s special is that they have unique qualities, such as “all scrolls will work on this item” or “100% chance of increasing potential rank”! There are different boxes for hats, overall/top/bottom, shoes/gloves, and weapon.