Secret Mastery Book...

so I got a secret mastery book from hot time.... what should I do with it? Like what would make me the most profit? Sell it unopened? Open it and sell it? Hold on to it for a long time and sell it unopened? I think I should hold on to it and sell it in a little while unopened... I may be wrong however what do you guys think?

I would open it and sell whatever is inside.


I enjoy gambling.

I believe it's best to sell it now for a high price unopened.

According to Spadow's blog, the secret books drop instead of the normal skill books now as part of the Chaos update (from bosses such as horntail)
So they will become MUCH less rare later on.