the answer is 20, you get one from bribing Alcyone (desert) and like 16-18 from bribing ghost in cavern of the stolen fayth. just go to desert with about 100k and juswt bribe alcyones 4301 (or double if itas not pal/international) if it misses just bribe for 1 each time.
ghosts same principle but 99991 then 1 everytime