When is a creature's toughness calculated

At what point is a creature's toughness calculated? If I have Korozda Guildmage where I can sacrifice a creature and put X 1/1 token creatures onto the battlefield, where X is the sacrificed creature's toughness.

If I have a creature that is 4/4 and cast Giant Growth to give it +3/+3 then sacrifice it? Do I get 4 tokens or 7?

Also what if my 4/4 creature was dealt 2 combat damage before I sacrificed it? Do I get 2 or 4 creatures?

Finally, what about counters? If my 4/4 had a +1/+1 do I get 4 or 5 tokens?

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Part of the confusion may arise from the fact that, if you've played Duels of the Planeswalkers on XBox (or whatever), a 4 toughness creature that's emerged from combat with a 2 power creature will now be displayed on screen as a 4/2. This is a little bit naughty, since actually it's still a 4 toughness creature, just one that can now only take 2 more damage before it dies. It's a convenient but ever so slightly misleading way of depicting the current game state... – thesunneversets Oct 15 '12 at 11:20

At what point is a creature's toughness calculated?

It's continually calculated. The real question is when does Korozda Guildmage's ability check the creature's toughness.

Korozda Guildmage's ability checks the creature's toughess as it resolves because it's not needed before then [CR 107.3e]. Since the creature no longer exists at that point, last known information is used [CR 112.7a]. Effectively, that means the total toughness of the creature at the time it was sacrificed is used.

If I have a creature that is 4/4 and cast Giant Growth to give it +3/+3 then sacrifice it? Do I get 4 tokens or 7?

7. Giant Growth increases the toughness of a creature.

Also what if my 4/4 creature was dealt 2 combat damage before I sacrificed it? Do I get 2 or 4 creatures?

4. It's a 4/4 with 2 damage marked on it. Damage does not reduce toughness. (Well, damage from a source with wither or infect can reduce toughness, but only indirectly, by virtue of giving -1/-1 counters.)

+1/+1 counters, -1/-1 counters and any other similar counters affect toughness.

If my 4/4 had a +1/+1 do I get 4 or 5 tokens?

5. Effects that modify toughness (such as Giant Growth's or Glorious Anthem's) modify toughness.

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Word for word rules given for the card Sworn Defender:

You apply power/toughness changing effects in a series of sublayers in the following order: (a) effects from characteristic-defining abilities; (b) effects that set power and/or toughness to a specific number or value; (c) effects that modify power and/or toughness but don't set power and/or toughness to a specific number or value; (d) changes from counters; (e) effects that switch a creature's power and toughness. This card's effect is always applied in (b), which means that effects applied in sublayer (c), (d), or (e) will not be overwritten; they will be applied to the new value.

This means that positive counters and Giant Growth will give you more tokens. (I know that the question was answered, but I wanted to give the verbatim explanation for it).

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Toughness is continually updated as effects change it. +X/+Y effects like Giant Growth change the toughness from the moment the effect is applied (so, starting right during the spell's resolution). +1/+1 or -1/-1 counters change the toughness from the moment they are placed on the creature. Anything else, as far as I can think of, does not affect the toughness; in particular, damage does not reduce a creature's toughness.

For an effect like Korozda Guildmage, when it refers to the toughness of a creature, that is always the current toughness, or if the creature has left the battlefield, the last toughness it had before leaving. The number printed on the card has no special meaning for a permanent in play.

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ah, looks like I forgot to finish writing before I submitted :-P – David Z Oct 15 '12 at 6:09

Toughness is calculated whenever State-Based Actions are checked, just before a player receives priority, and whenever else a spell ability asks for it.

704.2. State-based actions are checked throughout the game and are not controlled by any player.

704.3. Whenever a player would get priority (see rule 116, "Timing and Priority"), the game checks for any of the listed conditions for state-based actions ... This process also occurs during the cleanup step.

208.2a The card may have a characteristic-defining ability that sets its power and/or toughness according to some stated condition. (See rule 604.3.) Such an ability is worded "[This creature's] [power or toughness] is equal to ..." or "[This creature's] power and toughness are each equal to ..." This ability functions everywhere, even outside the game. If the ability needs to use a number that can't be determined, including inside a calculation, use 0 instead of that number.

Korozda Guildmage sacrifices creatures, and puts a number of 1/1 tokens into play based upon the creatures toughness. When the effect resolves, it cannot use the creatures current toughness, because the creature is no longer on the battlefield (and creatures do not exist anywhere except the battlefield, everywhere else they are creature spells or creature cards). So, it uses that objects Last Known Information.

608.2g If an effect requires information from the game (such as the number of creatures on the battlefield), the answer is determined only once, when the effect is applied. If the effect requires information from a specific object, including the source of the ability itself or a target that’s become illegal, the effect uses the current information of that object if it’s in the public zone it was expected to be in; if it’s no longer in that zone, or if the effect has moved it from a public zone to a hidden zone, the effect uses the object’s last known information.

So, for your individual questions, the toughness is calculated when the effect of Korozda Guildmage resolves. At this point, it uses the Last Known Information about the creature. This includes any effects that modify toughness (like Giant Growth that adds +3/+3 to the Power/Toughness, or counters that add/subtract from the P/T). Damage does not modify toughness, it is only marked on the creature to track lethal damage. So your answers are 7 (Giant Growth adds toughness), 4 (damage does not affect toughness), 5 (+1/+1 counters add toughness).

302.4c To determine a creature's power and toughness, start with the numbers printed in its lower right corner, then apply any applicable continuous effects. (See rule 613, "Interaction of Continuous Effects.")

613.3c Layer 7c: Effects that modify power and/or toughness (but don't set power and/or toughness to a specific number or value) are applied.

121.1a A +X/+Y counter on a creature or on a creature card in a zone other than the battlefield, where X and Y are numbers, adds X to that object's power and Y to that object's toughness. Similarly, -X/-Y counters subtract from power and toughness. See rule 613.3.

302.7. Damage dealt to a creature by a source with neither wither nor infect is marked on that creature (see rule 119.3).

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