UO Second Age

i could of sworn shelfs use to block line of sight, atm you can cast spells and throw pots through them, and can not hide behind them if your opp is on other side.

Shelves do not block LOS. I remember using as walls inside my house to prevent potions and spells from being targetable at me through the door, and it never worked. However, the bookshelves with BOOKS, in them will block your LOS, but they arent common (if they exist here) as an item, so it pretty much just protects your privacy if your in the brittan library.