Convoke loophole?

[Raging Badger]

If you are paying for a creature with convoke by tapping a creature that when you tap it gives you mana, will you get that mana and pay one to convoke?

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If you are paying for a creature with convoke by tapping a creature that when you tap it gives you mana, will you get that mana and pay one to convoke?

Nope. When you activate {elvish mystic}s ability to add a green to your pool that's all your doing. If you choose to tap for convoke, you cannot also tap for the activated ability.

[TheRagingMage]

The new wording in the reminder text is misleading, though.

It previously read: 702.50a: "For each colored mana in this spell's total cost, you may tap an untapped creature of that color you control rather than pay that mana. For each generic mana in this spell's total cost, you may tap an untapped creature you control rather than pay that mana."

Now it says: "Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color."

And if you tap a creature to activate its mana ability while casting the spell, it seems like it would cause both a mana and a cost reduction.

605.3a: A player may activate an activated mana ability whenever he or she has priority, whenever he or she is casting a spell or activating an ability that requires a mana payment, or whenever a rule or effect asks for a mana payment, even if it's in the middle of casting or resolving a spell or activating or resolving an ability.

Why did they change the wording?

EDIT: found this on the Wizards Community page:

Matt Tabak wrote:
The rules for convoke have changed slightly since it last appeared in an expansion. Previously, convoke reduced the cost to cast a spell. Under current rules, you tap creatures at the same time you pay the spell's costs. Tapping a creature this way is simply another way to pay.

[InfinitiveDivinity]

Why did they change the wording?

They're making it easier to understand for newer players.

[Remillo]

Why did they change the wording?

They're making it easier to understand for newer players.

It also changed the functionality slightly.  Convoke, along with delve, used to be methods of Cost Reduction.  Now, they function as forms of Payment.  While the change may not seem needed, it does allow for odd corner-case interactions, such as allowing you to still cast {Treasure Cruise} for U and exiling seven cards while {Trinisphere} is on the table.

As for convoke, the important part is an untapped creature.  If you've tapped for Elf for mana to cast it, it isn't untapped to tap for convoke.  It's as simple as that.  (However, you could tap a {Devoted Druid} to float a G, then untap it, then tap it again while casting your spell for convoke.)