Kinnan is a new card so I don't know if it's okay to ask yet or not, but I've seen some people saying that Urza's mana production is not increased because Urza is the source of the mana ability and isn't being tapped while I've seen others that say it is increased because there is a non-land permanent being tapped for mana.
As a follow up would Priest of Forgotten Gods have its mana increased. Priest doesn't have a mana ability, but it is being tapped to produce mana.
To tap a permanent for mana means to use a mana ability of that permanent that has a cost of tapping it specifically. So Urza is not being tapped for mana, even if he is turned into an artifact and his ability is used. Nor is any other artifact tapped for mana when using his ability. And so Kinnan doesn't care, he won't give extra mana.
106.12. To “tap [a permanent] for mana” is to activate a mana ability of that permanent that includes the {T} symbol in its activation cost. See rule 605, “Mana Abilities.”
Likewise, since Priest of Forgotten Gods ability is not a mana ability, it isn't tapped for mana, even though its ability's cost includes tapping it.
Kinnan is a new card so I don't know if it's okay to ask yet or not, but I've seen some people saying that Urza's mana production is not increased because Urza is the source of the mana ability and isn't being tapped while I've seen others that say it is increased because there is a non-land permanent being tapped for mana.
As a follow up would Priest of Forgotten Gods have its mana increased. Priest doesn't have a mana ability, but it is being tapped to produce mana.
Well, you could ask very similar questions replacing Kinnan with an existing card like Leyline of Abundance or Mana Reflection. This rule is relevant:
106.12. To “tap [a permanent] for mana” is to activate a mana ability of that permanent that includes
the T symbol in its activation cost. See rule 605, “Mana Abilities.”
106.12a An ability that triggers whenever a permanent “is tapped for mana” or is tapped for mana
of a specified type triggers whenever such a mana ability resolves and produces mana or the
specified type of mana.
106.12b A replacement effect that applies if a permanent “is tapped for mana” or tapped for mana
of a specific type and/or amount modifies the mana production event while such an ability is
resolving and producing mana or the specified type and/or amount of mana.
Urza, Lord High Artificer: That ability doesn't have T in its activation cost, so the ability won't trigger.
Priest of Forgotten Gods: That trigger event explicitly requires a mana ability, so the ability won't trigger, even if you happen to choose zero targets.
605.1a An activated ability is a mana ability if it meets all of the following criteria: it doesn’t require a target (see rule 115.6), it could add mana to a player’s mana pool when it resolves, and it’s not a loyalty ability. (See rule 606, “Loyalty Abilities.”)
115.6. A spell or ability that requires targets may allow zero targets to be chosen. Such a spell or ability is still said to require targets, but that spell or ability is targeted only if one or more targets have been chosen for it.
For a likely followup question, activating Holdout Settlement's "T, Tap an untapped creature you control: Add one mana of any color." counts as tapping Holdout Settlement for mana, but it doesn't count as tapping that creature for mana (because this isn't an ability of that permanent). So, this wouldn't trigger Kinnan from either permanent.
Kinnan, Bonder Prodigy
Kinnan is a new card so I don't know if it's okay to ask yet or not, but I've seen some people saying that Urza's mana production is not increased because Urza is the source of the mana ability and isn't being tapped while I've seen others that say it is increased because there is a non-land permanent being tapped for mana.
As a follow up would Priest of Forgotten Gods have its mana increased. Priest doesn't have a mana ability, but it is being tapped to produce mana.
Likewise, since Priest of Forgotten Gods ability is not a mana ability, it isn't tapped for mana, even though its ability's cost includes tapping it.
Former Rules Advisor
"Everything's better with pirates." - Lodge
(The Gamers: Dorkness Rising)
"Any sufficiently analyzed magic is indistinguishable from science."
(Girl Genius - Fairy Tale Theater Break - Cinderella, end of volume 8)
Well, you could ask very similar questions replacing Kinnan with an existing card like Leyline of Abundance or Mana Reflection. This rule is relevant:
Urza, Lord High Artificer: That ability doesn't have T in its activation cost, so the ability won't trigger.
Priest of Forgotten Gods: That trigger event explicitly requires a mana ability, so the ability won't trigger, even if you happen to choose zero targets.
For a likely followup question, activating Holdout Settlement's "T, Tap an untapped creature you control: Add one mana of any color." counts as tapping Holdout Settlement for mana, but it doesn't count as tapping that creature for mana (because this isn't an ability of that permanent). So, this wouldn't trigger Kinnan from either permanent.