How to use the Book of Tephery1 ?

[wikipedia]

Book of Tephery1: If you have this book in your inventory and when you try to make and it fail, you got all your items back in your inventory, except book.

but it's not working.

[Sakuya Izayoi]

I think it's supposed to be used while attempting to upgrade rare items.
If you have a certain amount of books and fail the upgrade, you keep the required rares and sardonyxes/leaves, but the books are lost regardless of outcome (even if you succeed).

Code: Select all

Rare Grade   Required rares    Max. success rate    Required Books of Tephery
        G2           G1 x 3                  80%                            1
        G3           G2 x 2                  60%                            2
        G4           G3 x 2                  40%                            2
        G5           G4 x 3                  34%                            3
        G6           G5 x 2                  30%?                           3
        G7           G6 x 2                  25%?                           4
        G8           G7 x 3               18-20%                            4
        G9           G8 x 2?                 15%?                           5
       G10           G9 x 2?                 10%?                           5

Please correct me if I'm wrong.

Source : http://www2.atwiki.jp/dragonraja/pages/64.html

[wikipedia]

I have bought 6 of the Tephery3 ,but being unable works as before.