Bront said:You know, I had a thread about this subject that almost came to blows (Fairly impressive on the net). Did you include the extra cost of the spell itself? I think an XP sucking spell costs extra (might be 1 gp per xp, but that bumps the cost up)
It costs 5 gp per XP that the casting wizard must use. That is the reason that the spell costs 28,325 rather than just 3,325 as any other 9th level spell would.