another rule question

[joemuz]

marek14 (or anyone else), cards like dark sphere or nova pentacle... must they be activated only when it is certain that its target will become a damage source? or can you just simply pick a target and have the effect apply the next time it would do damage?

in other words, obviously, if someone casts, say a fireball, you could activate nova pentacle (assuming there is a creature in play), but could you also activate it and choose something like a prodigal sorcerer as the damage source even if the sorcerer's ability is not currently being used and the pentacle's effect will occur if and when the sorcerer's ability is used during the current turn?

i know that in general, that would not be a very strategic use for it, but i'd still like to know. cards that say "the next time a source of your choice would deal damage to you..." always made me wonder.

i guess a succinct way to ask would be, must there be a damage dealing effect on the stack for cards like dark sphere or nova pentacle to be activated?

[Marek14]

marek14 (or anyone else), cards like dark sphere or nova pentacle... must they be activated only when it is certain that its target will become a damage source? or can you just simply pick a target and have the effect apply the next time it would do damage?

in other words, obviously, if someone casts, say a fireball, you could activate nova pentacle (assuming there is a creature in play), but could you also activate it and choose something like a prodigal sorcerer as the damage source even if the sorcerer's ability is not currently being used and the pentacle's effect will occur if and when the sorcerer's ability is used during the current turn?

i know that in general, that would not be a very strategic use for it, but i'd still like to know. cards that say "the next time a source of your choice would deal damage to you..." always made me wonder.

i guess a succinct way to ask would be, must there be a damage dealing effect on the stack for cards like dark sphere or nova pentacle to be activated?

Well, let's look at the rules:

608.7. Some effects apply to damage from a source—for example, “The next time a red source of your choice would deal damage to you this turn, prevent that damage.”

608.7a If an effect requires a player to choose a source of damage, he or she may choose a permanent; a spell on the stack (including a permanent spell); any object referred to by an object on the stack, by a replacement or prevention effect that’s waiting to apply, or by a delayed triggered ability that’s waiting to trigger (even if that object is no longer in the zone it used to be in); or, for certain casual variant games, a face-up card in the command zone. A source doesn’t need to be capable of dealing damage to be a legal choice. The source is chosen when the effect is created. If the player chooses a permanent, the effect will apply to the next damage dealt by that permanent, regardless of whether it’s combat damage or damage dealt as the result of a spell or ability. If the player chooses a permanent spell, the effect will apply to any damage dealt by that spell and any damage dealt by the permanent that spell becomes when it resolves.

608.7b Some effects from resolved spells and abilities prevent or replace damage from sources with certain properties, such as a creature or a source of a particular color. When the source would deal damage, the “shield” rechecks the source’s properties. If the properties no longer match, the damage isn’t prevented or replaced. If for any reason the shield prevents no damage or replaces no damage, the shield isn’t used up.

608.7c Some effects from static abilities prevent or replace damage from sources with certain properties. For these effects, the prevention or replacement applies to sources that are permanents with that property and to any sources that aren’t on the battlefield that have that property.

The 608.7a is what you want. Short version: Almost ANYTHING can be selected as damage source. Definitely any permanent, no matter whether it's capable of dealing damage or not.

[joemuz]

damn, its right there in the rules. i don't know how i missed it. i usually look through the comp rules first before posting but for whatever reason, i didn't see it.

anyway, that is very good news, as this is exactly the way i implemented dark sphere and nova pentacle should be trivial. thanks again.

[Marek14]

damn, its right there in the rules. i don't know how i missed it. i usually look through the comp rules first before posting but for whatever reason, i didn't see it.

anyway, that is very good news, as this is exactly the way i implemented dark sphere and nova pentacle should be trivial. thanks again.

Well, it's not THAT good news if you read the fine print. For example, you are allowed to choose as damage source a creature that is no longer in play (like Prodigal Sorcerer) if it's mentioned by anything on stack.

[joemuz]

ok but i was talking about the difference between allowing it to target ONLY things which are confirmed to be damage dealers, with allowing it to target nearly anything targetable. in other words, the difference between really not correct and almost correct. i know you know that that's really all that can be hoped for when coding on an ancient piece of software that was based on ancient rules.

[Marek14]

ok but i was talking about the difference between allowing it to target ONLY things which are confirmed to be damage dealers, with allowing it to target nearly anything targetable. in other words, the difference between really not correct and almost correct. i know you know that that's really all that can be hoped for when coding on an ancient piece of software that was based on ancient rules.

Except that there's, strictly speaking, no "targeting" as such. Damage sources are not targeted.

[joemuz]

right. when i was talking about "targeting" i was referring to it in programming context. within the confines of the ancient software, there's really only one way to pick something and that's by making it a "target." sorry for the confusion. though i would like to note that by setting the illegal_abilities parameter, it is possible to differentiate between actual "targets" and things that are chosen. and that's indeed what i did with dark sphere. it is possible, for example, to choose a creature with shroud as the damage source, since it is, as you said, strictly speaking, not a target.

[Marek14]

right. when i was talking about "targeting" i was referring to it in programming context. within the confines of the ancient software, there's really only one way to pick something and that's by making it a "target." sorry for the confusion. though i would like to note that by setting the illegal_abilities parameter, it is possible to differentiate between actual "targets" and things that are chosen. and that's indeed what i did with dark sphere. it is possible, for example, to choose a creature with shroud as the damage source, since it is, as you said, strictly speaking, not a target.

I see