Did a little testing after all of the complaining on the Cat2 thread about NIN merits.
I noticed some erratic behavior during the testing, of course it's also possible that it's not linear. This was done with war subjob on earthsday and varying amounts of int on the level 1 worms in Gustaberg right near the Mines exit. Damage is 2 higher than it should be because I have 1 hyoton damage merit.
total int - damage
65 189
66 190
67 192
68 193
69 195
70 196
71 198
72 199
73 201
74 202
75 205
76 206
77 208
78 209
79 211
Interestingly if I take the first two and the last 2 data points, assume mob int=0 (not correct) and M=1.5, I get V=8.95 and V=90.5. I think V=90 is a fairly good guess.
You'll notice from 74 to 75 the damage jumped 3 points instead of 2. Very consistent pattern of 1 then 2 jump other than that. I redid those datapoints several times to see if I made an error (hit the wrong mob, etc) and no, I didn't.
Turns out that because of the low base damage, INT is actually better than MAB at first. MAB merely gives a 1% damage bonus, and +1.5 is more than 1% when the base damage is only 90.
It's very easy to get a high INT & MAB build for a 75 NIN. With pieces like Kirin's Osode (10 int) and Uggalepih Pendant (due to the MP activation it can be active all the time) you can easily pump up the damage quite a bit. A nice MP-less nuke every 60 seconds with the right gear swapped in could probably do 300 damage without a ton of effort.
EDIT: ^ Speculation turned out to be incorrect. 300 damage is easily done on lower level mobs, but when you start fighting things with high INT things change drastically.
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