[SephirothYuyX]

damage=[( (your INT- enemy INT) x multiplyer)+elemental D parameter] x (multiplyer 2) x (bonus damage from day)

multiplyer 1:
I 1.0
II 1.0
III 1.5
IV 2.0
ancient 2.0
elemental staff +0.10(NQ) or +0.15(HQ)

so if you use ICE 3+equip elemental staff NQ with you will get 1.65 for your multpyer 1

multiplyer 2
this is from your passive skill magic damage up
BLM
10 1.2
30 1.24
50 1.28
70 1.32
eariing from NM +0.05
so level 70 blm with earing will get 1.37

bonus:elemen mach the day will increase 10% opposit elemental will decrease 10%

Elemental D

Earth: I:5 II:78 III:210 IV:381 Ancient: 577
Water: I:11 II:90 III:236 IV:410 Ancient:630
Aero:I:20 II:108 III:265 IV:440 Ancient:552
Fire: I:30 II:128 III:295 IV:472 Ancient:657
Ice: I:41 II:150 III:320 IV:506 Ancient:526
Thunder: I:55 II:137 III:345 IV:541 Ancient:603