When your with the villains, your one of their soldiers, ranking up as your power increases to it, the class doesn't matter to them, only victory, you can even have the planets race you take over as their slaves.
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They start with the skill for each:

Offence learns deadly blow; an ability to use that tickles the person at one spot that triples the damage, for defences is double the damage, they can use it again for 5 turns or when it's over.

Defence learns Counter strike; as the enemy strikes a second away, they immediately dodge it and tickle a spot of their choosing, doubling the damage, only using it again for another 3 turns or until the fight is over.

Specialist learns downgrade; this skill is used to disable the hero suit, making all their enemy stats in half, only being able to use it once per battle, so they have to choose wisely.
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More details will be added later