Just confirming what Melodia reported, in that if you have Dimensional Ripper and 0 cards in your deck, attacking your opponent will cause you to take 1 damage.
If you have a full hand, you don't take damage from forced draws because you're not doing any drawing. So in Dimensional Ripper and a 0 card deck, your opponent is the one drawing from your library, not you, so he should be taking that damage instead of you.
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