INT vs MAB

At Level 75, a fairly common rule of thumb is that “2INT ≈ 1MAB,” which has been largely shown to be true from general observation.

A much more accurate figure can be derived using the following formula to solve the equation ???INT = 1MAB,

\[\triangle I_Y=\frac{\frac{B}{\lambda}+I_Y-I_M}{M+100} \]

To use, simply plug in your known values for each of the variables. For example, if I were to nuke Thunder IV (541 base damage, tier modifier is 2) on an Ebony Pudding (89INT) with gear that gets me 125INT and 71MAB, I get:

\[\triangle I_Y=\frac{\frac{B}{\lambda}+I_Y-I_M}{M+100}=\frac{\frac{541}{2}+125-89}{71+100}=1.792 \]

Therefore I need approximately 1.8INT to match 1MAB’s worth of damage.

Mathematical support

The damage formula is as follows:

\[D=k(1+\frac{M}{100})[B+\lambda(I_Y-I_M)]\]

• k = product of all the modifiers from elemental staves, day, weather, magic burst and type of mob.
• M = total Magic Attack Bonus from both Job Traits and equipment.
• B = Spell’s base damage.
• λ= Nuke’s tier modifier.
• I = Total intelligence (base INT and gear). Subscript refers to either You, or the Mob.

Through algebraic manipulation, the two partial derivatives of the above equation with respect to your Intelligence and to your Magic Attack Bonus work out to be,

\[\frac{dD}{dI_Y}=\frac{\lambda k(M+100)}{100}\]
\[\frac{dD}{dM}=\frac{k[B+ \lambda (I_Y-I_M)]}{100} \]

By the principle of small changes, we can write

\[\frac{dI_Y}{dI_M}=\frac{\triangle I_Y}{\triangle M} \]

Therefore as ∆MAB=1,

\[\triangle I_Y=\frac{dI_Y}{dM} \]

Then, use the chain rule with the two partial derivatives to derive dI/dM:

\[\triangle I_Y=\frac{dI_Y}{dM}=\frac{dI_Y}{dD}\frac{dD}{dM} \]
\[\triangle I_Y=\frac{dI_Y}{dM}=\frac{100}{\lambda k(M+100)}\frac{k[B+\lambda (I_Y-I_M)]}{100} \]

Finally, simplify the expression.

\[\triangle I_Y=\frac{\frac{B}{\lambda}+I_Y-I_M}{M+100} \]