Book of Darkness

I got 3 Book of Darkness in just 7 attempt now I don't know what to do with it
Any suggestions?
If I'll gonna use it for my character what weapon and skills with build you suggest?

 

1. Sell immediately.
2. Hold on to it and sell later when price is higher.
3. Use it on your character.
4. Give it away.

If you're gonna use it, I recommend using it on STR-based builds like ohs/ths/halberd/katana builds. Bowgun builds could also use it for Soul Hunter since they lack i-frame skills. The main thing you're gonna use from that skill tree are Eternal Nightmare and Soul Hunter. Some people might invest on Regretless for AMPR & resistance buff. And then there are those non-meta builds that make use of Dark Stinger and such. You just gotta look around YouTube for some demo.

 

Thank you so much^^

 

VIT builds work too.
Dark Stinger scales on both, STR and VIT.
Sacrifice deals special damage proportional to your maxHP.

some skills, such as Red Tear, deal magic damage but still use the atk stat.
so while physical builds generally get more out of the skills, magic users can still get some utility from it.
Soul Hunter is a universal skill with different bonus effects for every weapon.