You should gain 1 MP for every 10 INT when you add AP into MP. I had 400int on my bm and added APs into MP, but I only got the normal amount, no extra for the INT. Should have gotten 50MP'ish per AP but I only got 10. The amount you get isn't exactly right, but it is what most pre-bb gMS discussions mention. Other private servers have the same kind of approximation for the formula as well. Also, can't reset the APs I added into MP on my priest. And didn't get any extra MP from having INT on that character either. Nor did I get any extra mp from improved maxmp increase skill, which is supposed to give you 2 x skill lvl for every AP you add into MP. I should have got 18~20 + 40 (had 400int on my mage as well when I tested it) + 20 (improved maxmp increase lvl 10) = 78~80, so I lost 60mp'ish per AP, used two.
