Where can I find Lv 30 Berserk?

Not buying because I have no meso.
I need to know wich mob it drops.
I heard it was only Horntail and that would just be... extremely unfair if you ask me.
Those books cost way to much for me + they're only 50% chance
(wich is if you knew me nearly impossible to pass for me xD)

So yeah, does anyone know? I've tried google but couldn't find anything on there either.

Secret Mastery Book.

Secret Mastery Book.

Another luck based chance. How small is the chance of getting one out of that? 1/1000?
But yeah thanks for letting me know (No sarcasm) I forgot about those things.
But isnt there a mob who purely drops Berserk 30?

Another luck based chance. How small is the chance of getting one out of that? 1/1000?
But yeah thanks for letting me know (No sarcasm) I forgot about those things.
But isnt there a mob who purely drops Berserk 30?

not anymore Nexon has made everything easier for everyone to get their new mastery books! All you need to do is get a secret mastery book and be very very very very very very very lucky!

1/195 chance.

some mobs might drop it, but you have to find one first before you know what drops it