# Which damage number does lifelink use to determine the life gain?

I have recently began playing a deck that has a number of creatures with lifelink in it. I want to be certain I understand the mechanic and the following question occurred to me.

Which damage total do you use to determine the life gain from lifelink? I had assumed that if a 3/3 creature with lifelink was blocked by a 2/2 creature that the life gain total would be 2, the maximum that the blocker can absorb before dying. This seems to be incorrect, as when I read the example attached to CR 119.4c

[...] attacks with a 3/3 creature with wither and lifelink. It’s blocked by a 2/2 creature, [...]. The damage event starts out as [3 damage is dealt to the 2/2 creature, 2 damage is dealt to the 3/3 creature]

Have I been short changing myself?

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It's not really a question of which damage number is used to determine life gain, because there is only one damage number. As the answers explain, in your example, a 3/3 creature deals 3 damage, period. The toughness of the blocker, 2, is not an amount of damage. –  David Z Jan 3 '12 at 17:58

Yes, you've been shortchanging yourself!

702.14b Damage dealt by a source with lifelink causes that source's controller, or its owner if it has no controller, to gain that much life (in addition to any other results that damage causes).

A creature with 10 power blocked by a creature with 1 toughness deals 10 damage to that poor little blocker. Creatures with 10 power are not known for their discretion or moderation; they don't deal 1 damage on the grounds that that will be enough to do the job. No, they smash that blocker into smithereens and leave behind a smoking crater!

I think your confusion may arise from the old card Drain Life, whose text reads:

Drain Life deals X damage to target creature or player. You gain life equal to the damage dealt, but not more life than the player's life total before Drain Life dealt damage or the creature's toughness.

Drain Life is the exception though, not the rule; for lifelinkers the creature's toughness is irrelevant in determining how much life is gained. (See also though Abattoir Ghoul, a recent card which offers a kind of new spin on the Drain Life idea.)

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Note that the blocking creature need to be in combat for your creature to do damage (unless it has trample as well). Also note that if you have double strike and the first strike kills the other creature, it will not strike again. –  AndSoYouCode Jun 21 '12 at 6:01
In Drain Life's case, it's not even a question of hidden rules. It's a limitation that is actually part of the card's text. –  rahzark Aug 6 '12 at 8:59