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Historical Rules · 5 October 2018

Rule 119.8

Official source text from the 5 October 2018 Rules release

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If a source would deal 0 damage, it does not deal damage at all. That means abilities that trigger on damage being dealt won’t trigger. It also means that replacement effects that would increase the damage dealt by that source, or would have that source deal that damage to a different object or player, have no event to replace, so they have no effect.

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