I know INT was used in the later dragon quest games(8 and 9) to scale damage and success rate of certain skills but does this apply to 7? Will Additional INT increase spell damage or is it used entirely for the contest ranking?
Int has nothing to do with spell damage. Though there is speculation, and I've had experiences where it seems like higher int from DQ5-7 means more higher end of the damage spectrum, but further analysis says it's just the RNG favouring me in those moments.
As for what it actually does, aside from the Contest? It helps prevent status effects, and so far that's all I know. It could increase the chance to dodge spells, but I haven't seen anything like that beyond status effect spells, which comes right back to Status Effects; skill or spell.
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