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I'm the farthest thing from a magic know it all, so I have a question for you. If my opponent has a 40/40 with trample and I have a 20/20 with lifelink that is blocking it. and I have 20 life left. Do I gain life from lifelink at the same time the damage is dealt to me? Thanks for taking the time to answer!

marked as duplicate by Nuclear Wang, KSFT, diego, SocioMatt, doppelgreener Oct 4 '16 at 19:43

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  • You do but still end up at 0 life ;) – Stephane Oct 7 '16 at 22:33
  • @Stephane no you don't. Your 20/20 blocks the 40/40, soaking up 20 of the damage, the other 20 goes to your life. Your 20/20 gives you 20 life for the damage it dealt, which in effect cancels out the rest of the damage, so you end up at 20 life since 20-(40-20)+20=20 – Andrew Dec 30 '17 at 16:18
  • My bad. You're right. – Stephane Dec 30 '17 at 22:33

Yes, lifelink is not a triggered ability like you might expect but a static replacement effect that replaces damage being dealt with the damage being dealt and you gaining that much life:

119.3f Damage dealt by a source with lifelink causes that source’s controller to gain that much life, in addition to the damage’s other results.

702.15a Lifelink is a static ability.

Note that this is not the case with cards that say "Whenever this card deals damage, you gain that much life"; that would be a triggered ability, and you would lose before it could resolve.

  • 1
    While the conclusion is correct, I'm pretty sure Lifelink is not a replacement ability. It modifies the normal result of damage being dealt in the same way infect does. – GendoIkari Oct 4 '16 at 20:56

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