The rules prevent any C value being boosted above 9.
Darius has a defence value of 3 as stated in the army list.
He is not a Superior Fighter as it does not say he is.
He is a Commander, not a unit, so is not formed or unformed. As a special rule he can be attacked, by any troops, and he does not charge or counter-charge.
Darius moves as a heavy chariot.
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