Re: Does this work in 6e?
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the way it's built, it seems to be "powered" (for lack of a better word) by the drain. That being the case, is he getting more dice of knockback than he is "earning" via the drain?
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My thinking was that the Dispel "effect" is what's rolled on the dice, and that's what's used for purposes of knockback. It shouldn't matter how much KNB resistance they have, just as it doesn't matter how much body a target has when calculating how much body your Blast attack does.
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And as-presented, it seems to be useful only against characters with knockback resistance
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Yes, that was the idea. See my post above about adding "Expanded Effect" to cover Growth and DI.