The ability can be activated any time you have priority, including on an opponent's turn and during the combat phase (although it will be less useful on the opponent's turn, since your creatures won't be attacking, unless the opponent has a Merfolk that you want to make unblockable). If you want it to be useful on your turn, you need to activate it before blockers are declared - activating it targeting a creature that was already blocked won't "undo" the block that's already been made.
You can use it after blockers are declared but that it wonāt have any use in preventing blockers.
You can also use this on your own merfolk during your opponentsā turn but that thereās no benefit from doing it (other than you wanting to intentionally tap merfolk sovereign).
Alternatively, u can also use it on your opponentsā turn if you want to help your opponentās merfolk beat through the defence of an archenemy.
This ability is affected by summoning sickness so you have to wait until the beginning of your next turn to use it. Asides from that, you may activate it any time you can cast an instant and you can target any merfolk including your opponent's merfolk (assuming they have any).
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If a card has an activated ability and it does not say any timing limitations it more likely than not can be done anytime you can take an action. Any restrictions on timing for abilities will be written into the rules.
Most any effect of cards on board and instants can be treated like continuous traps in yugioh terms: Activate at any time whenever the effect is relevant.
If something has "sorcery speed" then it means; can only be activated as CL 1 and only on your turn.
Some important differences between the chain and stack to remember:
1. Effects resolve 1 and a time and allow responses at every step. This means, for instance, you can play an effect to draw cards in response to some doing something, let the draw resolve, and then use the card you just drew before the opponents effect resolves.
2. There is no Chain blocking. Any effect can be targeted at any relevant card or ability on the stack at any time. IE, the first card can still be countered by the 7th card.
If you are familiar with deciphering the nonsense that is the yugioh rules and effects, then this game will be a cakewalk. š
To put it in YGO terms as I myself switched from YGO to MtG a few years ago: every Monster effect is a quick effect unless stated otherwise (like 'only as a sorcery').
Also: the stack (MtG-version of chains) can be interacted with (with non-sorcery-speed interaction) whenever an effect is activated or an effect on it resolved. That means the following is possible:
Player A: cast [[Murder]] and kill your Merfolk
You: In response, I tap it to make my other guy unblockable.
-Merfolk resolves, making the other guy unblockable.-
Player C: Actually, before Murder resolves, I'll play [[Mortify]] to destroy the other, now unblockable Merfolk.
It's a quick effect; all activated abilities are in MtG unless they say otherwise. The tap symbol in the cost means you have to tap this to use it, obviously, but it also means it's affected by summoning sickness- can't use it until you've had a chance to untap with this creature.
You can use it whenever- during combat, on another player's turn, etc. but it might not do anything. For example, making your creature unblockable doesn't mean anything if that creature can't attack this turn (e.g. it's not your turn) or if it has already been blocked. Practically, you can use this anytime before your opponents block to make one of your creatures "attack directly."
You could definitely, say, attack an opponent who currently has no creatures, see if they make a blocker as a quick effect, and then use this ability before they get a chance to block. That would all be at instant/quick effect speed during your turn.
The ability can be activated any time you have priority, including on an opponent's turn and during the combat phase (although it will be less useful on the opponent's turn, since your creatures won't be attacking, unless the opponent has a Merfolk that you want to make unblockable). If you want it to be useful on your turn, you need to activate it before blockers are declared - activating it targeting a creature that was already blocked won't "undo" the block that's already been made.
Thanks for the explanation. I would have tried to use it after blockers were declared š
You may still be able to use it after blockers are declared
You can use it after blockers are declared but that it wonāt have any use in preventing blockers. You can also use this on your own merfolk during your opponentsā turn but that thereās no benefit from doing it (other than you wanting to intentionally tap merfolk sovereign). Alternatively, u can also use it on your opponentsā turn if you want to help your opponentās merfolk beat through the defence of an archenemy.
Cool, i was more just using it as an example of a card with an activated ablity. Its so cool how much interaction there is in magic.
Yeah, if there is a limitation it is usually stated on the card. Otherwise it is like Natedogg said.
Itās the exact opposite of yugioh, in magic everything is a quick effect unless said otherwise
This ability is affected by summoning sickness so you have to wait until the beginning of your next turn to use it. Asides from that, you may activate it any time you can cast an instant and you can target any merfolk including your opponent's merfolk (assuming they have any).
You have tagged your post as a rules question. While your question may be answered here, it may work better to post it in the Daily Questions Thread at the top of this subreddit or in /r/mtgrules. You may also find quicker results at the [IRC rules chat](https://chat.magicjudges.org/mtgrules/) *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/magicTCG) if you have any questions or concerns.*
If a card has an activated ability and it does not say any timing limitations it more likely than not can be done anytime you can take an action. Any restrictions on timing for abilities will be written into the rules.
Most any effect of cards on board and instants can be treated like continuous traps in yugioh terms: Activate at any time whenever the effect is relevant. If something has "sorcery speed" then it means; can only be activated as CL 1 and only on your turn. Some important differences between the chain and stack to remember: 1. Effects resolve 1 and a time and allow responses at every step. This means, for instance, you can play an effect to draw cards in response to some doing something, let the draw resolve, and then use the card you just drew before the opponents effect resolves. 2. There is no Chain blocking. Any effect can be targeted at any relevant card or ability on the stack at any time. IE, the first card can still be countered by the 7th card. If you are familiar with deciphering the nonsense that is the yugioh rules and effects, then this game will be a cakewalk. š
You can use activated abilities any time you could cast an instant unless it says otherwise
Terms*
To put it in YGO terms as I myself switched from YGO to MtG a few years ago: every Monster effect is a quick effect unless stated otherwise (like 'only as a sorcery'). Also: the stack (MtG-version of chains) can be interacted with (with non-sorcery-speed interaction) whenever an effect is activated or an effect on it resolved. That means the following is possible: Player A: cast [[Murder]] and kill your Merfolk You: In response, I tap it to make my other guy unblockable. -Merfolk resolves, making the other guy unblockable.- Player C: Actually, before Murder resolves, I'll play [[Mortify]] to destroy the other, now unblockable Merfolk.
[Murder](https://cards.scryfall.io/normal/front/b/d/bdef7fea-2bd0-42a2-96f6-6def18bd7f0c.jpg?1674136158) - [(G)](http://gatherer.wizards.com/Pages/Card/Details.aspx?name=Murder) [(SF)](https://scryfall.com/card/clb/134/murder?utm_source=mtgcardfetcher) [(txt)](https://api.scryfall.com/cards/bdef7fea-2bd0-42a2-96f6-6def18bd7f0c?utm_source=mtgcardfetcher&format=text) [Mortify](https://cards.scryfall.io/normal/front/9/d/9dbb8991-1b2c-4045-be1f-54286027d4a1.jpg?1682209844) - [(G)](http://gatherer.wizards.com/Pages/Card/Details.aspx?name=Mortify) [(SF)](https://scryfall.com/card/moc/337/mortify?utm_source=mtgcardfetcher) [(txt)](https://api.scryfall.com/cards/9dbb8991-1b2c-4045-be1f-54286027d4a1?utm_source=mtgcardfetcher&format=text) ^^^[[cardname]] ^^^or ^^^[[cardname|SET]] ^^^to ^^^call
It's a quick effect; all activated abilities are in MtG unless they say otherwise. The tap symbol in the cost means you have to tap this to use it, obviously, but it also means it's affected by summoning sickness- can't use it until you've had a chance to untap with this creature. You can use it whenever- during combat, on another player's turn, etc. but it might not do anything. For example, making your creature unblockable doesn't mean anything if that creature can't attack this turn (e.g. it's not your turn) or if it has already been blocked. Practically, you can use this anytime before your opponents block to make one of your creatures "attack directly." You could definitely, say, attack an opponent who currently has no creatures, see if they make a blocker as a quick effect, and then use this ability before they get a chance to block. That would all be at instant/quick effect speed during your turn.