Recent (and Minor) Rules and Wording Changes

Pursuit of Knowledge card art

Wizards is always tweaking rules and wording on its cards. This post covers things that have happened from the release of Foundations (2024) to present.

Foundations

Foundations was Magic's first core set in several years, and will be Standard-legal for five years, living up to its name. Wizards viewed this set as a milestone release, and used the opportunity to make some tweaks. From its release notes:

In the grand tradition of releases like Sixth Edition and Magic 2010, we're touching up the rules in order to make Magic easier to approach without compromising its strategic depth. With the release of Magic: The Gathering Foundations, we're removing combat damage assignment order from the game. Some of you remember the introduction of combat damage assignment order with the release of Magic 2010, which happened in conjunction with combat damage no longer using the stack (If you don't know what that means, don't worry; you won't have to learn about it!).

As the quote concludes, I won't explain what this is for the unfamiliar. But I will say that tweaks like this are meant to make the game more intuitive, and are often successful in so doing (the only people I've seen rant against these are those who exploit and unintuitive rule nuance).

Two other things to note about Foundations:

While the cards in Magic: The Gathering Foundations are intended to be played and drafted by players of all experience levels, we've taken some measures to help clarify existing keyword mechanics for new and returning players. Specifically, we've added reminder text to even Magic's most common mechanics in order to ensure a fun and understandable play experience.

This is nice. Seasoned players have evergreen keywords down pat, but for newbies, having an ability described on the card is a help.

With the release of Magic: The Gathering Foundations, we're making a few non-functional changes to card templating in order to improve clarity. Most are minor, but one is prolific and thus worth mentioning here: we're reducing the usage of card names in rules text. This will make it clearer that abilities that referred to the object they're on by the card's name apply only to that object and not other objects that have the same name. Instead of the card's name, you'll often see phrases like "this creature," "this spell," "this card," or "this Aura," depending on the card's type or subtype, the nature of the ability, and the zone or zones where the ability applies. Some exceptions exist, the most notable being legendary permanents, which will continue to use their names (or shortened forms of their names) in rules text. 

This is minor but important. Magic cards used to have the card name written out in the ability text where necessary. Llanowar Visionary is an example. 

Its printed text (as it released before Foundations) is shown: "When Llanowar Visionary enters the battlefield, draw a card." If it gets reprinted, it will say "When this creature enters, draw a card." (Recall that "enters the battlefield" became "enters" with the release of Bloomburrow.)

Aetherdrift

No new rules or wording changes; new mechanics and keywords for Aetherdrift (Speed, Start Your Engines!, and Max Speed) are covered in its release notes.

Tarkir: Dragonstorm

No new rules or wording changes; new mechanics, keyword abilities, keyword actions, and ability words for Dragonstorm (Omen cards, Harmonize, Mobilize, Behold, Endure, Renew, Flurry) are covered in its release notes.

Final Fantasy

Final Fantasy introduced a new land type (Town), but as with Gates, it has no inherent meaning unless referred to by another card.

This set also introduced Saga creatures, which are enchantment creatures. This can attack like normal creatures, but also have chapter-specific abilities that resolve as stated on the card. When the final lore counter is put on the sage, the ability resolves and the creature is sacrificed. But note the rules:

Speaking of Sagas, we’re making a small but impactful rules update with this release. With the advent of Saga creatures, it’s much easier to get into a situation where a Saga on the battlefield loses all of its abilities but is still a Saga enchantment. The result of this interaction was previously unintuitive to many players: since that Saga had no chapter abilities, the game defined the “greatest number among its chapter abilities” as zero, and no matter how many lore counters that Saga had on it, it would be sacrificed as a state-based action once it wasn’t the source of a chapter ability on the stack (usually right away). 

Starting with the release of Magic: The Gathering®—FINAL FANTASY, we’re updating the rules: If a Saga has no chapter abilities, it won’t be subject to the state-based action that would cause it to be sacrificed due to how many lore counters it has. Similarly, it won’t be subject to the turn-based action that adds a lore counter to each Saga you control at the beginning of your first main phase each turn. For example, if your Summon: Bahamut with one lore counter on it loses all abilities because someone attaches Observed Stasis to it, it’ll won’t gain lore counters via the turn-based action until it has chapter abilities again (probably because you removed the Observed Stasis somehow.)  

No other new rules or wording changes; new mechanics and keyword abilities for Final Fantasy (Saga Creatures, Job Select, Tiers) are covered in its release notes.

Edge of Eternities

Edge of Eternities introduced no new rules but a few new card types (Spacecraft artifacts and Planet lands). New mechanics and keyword abilities (Station, Warp, Void) are covered in its release notes.

Marvel's Spider-man

No new rules or wording changes; new keyword abilities for Spider-man (Web-slinging, Mayhem, ∞) are covered in its release notes.

Avatar: The Last Airbender

No new rules or wording changes; new keyword abilities and keyword actions for Avatar (Firebending, Earthbend, Waterbend, Airbend) are covered in its release notes.

Lorwyn Eclipsed

No new rules or wording changes; new keyword actions and ability words for Eclipsed (Blight, Vivid)  are covered in its release notes.

Mechanic: Forage

I conclude "mechanic March" by looking at forage. Like other mechanics examined this month, it involves the graveyard.

From the official rules,

701.59. Forage 

- 701.59a To forage means “Exile three cards from your graveyard or sacrifice a Food.”

Aside: forage refers to "Food." This is an artifact token:

111.10b A Food token is a colorless Food artifact token with “{2}, {T}, Sacrifice this artifact: You gain 3 life.”

Forage is a new mechanic, featured only in Bloomburrow (2024) on seven cards (all green and/or black). It is always presented as an optional ability, and sometimes only a possibility when a creature enters.

Forage is effectively an additional cost/benefit mechanism. To take advantage of forage's benefit, you need to pay the cost: either 1) have enough cards in your graveyard to exile or 2) have food tokens to sacrifice. Plenty of cards (in Bloomburrow and other sets) synergize well to get cards into your graveyard or create food tokens.

Being new, the forage card pool is small. That said, I like the mechanic and having two options to trigger it; that kind of flexibility can be huge.

Mechanic: Surveil

Continuing 'mechanics March,' today I look at surveil.

From the official rules,

701.42. Surveil 

- 701.42a To “surveil N” means to look at the top N cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.

Surveil is handy for two reasons:

1) getting through your deck faster to obtain desired cards (a deck sculpting mechanism)

2) getting cards into your graveyard faster to enable strategies that profit from that (delve pairs well)

The concept of surveil first appeared in Odyssey (2001), but it got its ability word starting in the Guilds of Ravnica (2018). It has appeared on 155 cards so far; the majority are blue and/or black.

Surveil is a powerful and popular mechanic, now featured to some degree in at least a few cards in sets each year.

Mechanics: Persist & Wither

Continuing 'mechanics March,' today I look at two (related) abilities: persist and wither. Both were first seen (and almost exclusively remain in) the Shadowmoor and Eventide (2008) sets. Both introduced a -1/-1 counter.

Persist

From the official rules,

702.79. Persist 

- 702.79a Persist is a triggered ability. “Persist” means “When this permanent is put into a graveyard from the battlefield, if it had no -1/-1 counters on it, return it to the battlefield under its owner’s control with a -1/-1 counter on it.”

In essence, this ability "can return a creature from the graveyard to the battlefield." And since you don't pay its mana cost the second time, it's like getting two-for-one. 

Intuitively, cards with powerful 'Enter the Battlefield' abilities profit from persist. The examples below show various ways it has been implemented (note the removal abilities of several).

To date, 31 cards have the persist mechanic, spread fairly evenly across all five colors. 

Wither

From the official rules,

702.80. Wither 

- 702.80a Wither is a static ability. Damage dealt to a creature by a source with wither isn’t marked on that creature. Rather, it causes that source’s controller to put that many -1/-1 counters on that creature. 

Wither is a way to make a creature's power count in combat, even if it isn't enough to destroy the other creature. Since normally damage on a creature is removed at the end of the turn (if it is not enough to destroy it), wither is way for the little guys to erode bigger creatures over several turns. And since it uses counters, mechanics like proliferate pair well with it.

To date, 35 cards have the wither mechanic, largely in black, red, and/or green colors.

-1/-1 counters aren't as common as their inverse (+1/+1 counters), but you can use them powerfully with a little planning. 

Mechanic: Delve

I kick off a new theme today: "mechanic March," where I look at various mechanics the game has featured over the years. (Note: these are technically 'keyword abilities'; the terms are often used interchangeably.) Today: delve.

From the official rules:

702.66. Delve 

- 702.66a Delve is a static ability that functions while the spell with delve is on the stack. “Delve” means “For each generic mana in this spell’s total cost, you may exile a card from your graveyard rather than pay that mana.” 

- 702.66b The delve ability isn’t an additional or alternative cost and applies only after the total cost of the spell with delve is determined. 

- 702.66c Multiple instances of delve on the same spell are redundant.

The glossary puts it more succinctly:

Delve: A keyword ability that lets you exile cards from your graveyard rather than pay generic mana to cast a spell. See rule 702.66, “Delve.”

Note delve affects only generic mana; you cannot use it for colored mana costs.

Delve is a cost reduction mechanic. For that reason, some delve cards have a higher printed cost than non-delve equivalents, so it makes sense to play the card only if you have cards in your graveyard to exile. Murderous Cut (below) is one example.

Delve was first seen in the Future Sight expansion (2007), though the Tarkir block (2014-15) features the most cards with that keyword. To date, 27 cards have this mechanic. Most are blue or black.

The delve mechanic is most efficient when you are playing a 'self-mill' deck, using other spells that put lots of cards into your graveyard. Cards like Stitcher's Supplier (below), for example, synergize well. And other mechanics (like surveil) pair well with it, too. Anything that puts cards in your own graveyard are fair game here.

Since so few cards have the delve mechanic today, I don't know how popular it is. But it is an option to be aware of for certain deck types.

Zones

Jaded Analyst card art

Today I wrap up the month looking at zones. 

From the official rules, 

400.1. A zone is a place where objects can be during a game. There are normally seven zones: library, hand, battlefield, graveyard, stack, exile, and command. Some older cards also use the ante zone. Each player has their own library, hand, and graveyard. The other zones are shared by all players.

I'll ignore the ante zone, as that has long been obsolete.

Zones can be public or private (see 400.2). Some cards can move between zones, but some cannot (see 400.4). "An object that moves from one zone to another becomes a new object with no memory of, or relation to, its previous existence." [with some exceptions; see 400.7] *note: this is an important concept in blink decks.

Most zones are intuitive:

- library: your face-down deck from which you draw cards. "When a game begins, each player’s deck becomes their library."

- hand: "where a player holds cards that have been drawn."

- battlefield: where all permanents exist once they are successfully cast

- graveyard: where cards go after being cast (instant, sorcery), destroyed (land, creature, artifact, enchantment, etc.), or discarded/milled (any card type).

- stack: where spells go before they resolve. I covered that in a separate post

- exile: "essentially a holding area for objects. Some spells and abilities exile an object without any way to return that object to another zone. Other spells and abilities exile an object only temporarily."

- command: "a game area reserved for certain specialized objects that have an overarching effect on the game, yet are not permanents and cannot be destroyed."

Let's take a closer look at the command zone, focusing on the Commander format.

903.6. At the start of the game, each player puts their commander from their deck face up into the command zone. 

903.8. A player may cast a commander they own from the command zone. A commander cast from the command zone costs an additional {2} for each previous time the player casting it has cast it from the command zone that game. This additional cost is informally known as the “commander tax.” 

903.9. A commander may return to the command zone during a Commander game. 

That last line is important. Uniquely, a commander can come out of the graveyard, exile, hand, or library to go back into the command zone:

903.9a If a commander is in a graveyard or in exile and that object was put into that zone since the last time state-based actions were checked, its owner may put it into the command zone. This is a state-based action. See rule 704. 

903.9b If a commander would be put into its owner’s hand or library from anywhere, its owner may put it into the command zone instead. This replacement effect may apply more than once to the same event. This is an exception to rule 614.5. 

Zones are intuitive outside of some moving between zone and commander nuances.

Evergreen Actions

Fblthp, Lost on the Range card art

Continuing the series, today I look at evergreen actions (I would say "terminology"). I will use MTG Wiki's list.

An action is something the game instructs you to do. Per MTG Wiki, there are 18 evergreen actions, 13 of which have been used since Alpha (the first set) but only 8 of which have been keyworded since Alpha. These terms are covered in glossary of the official rules and assume you know the zones of the game (which I mention here). Below, quotes from said rules are in italics.

- Activate (To put an activated ability onto the stack and pay its costs, so that it will eventually resolve and have its effect.)

- Attach (To take an Aura, Equipment, or Fortification from where it currently is and put it onto a specified object or player.)

- Cast (To take a card from where it is (usually the hand), put it on the stack, and pay its costs, so that it will eventually resolve and have its effect)

- Counter (1. To cancel a spell or ability so it doesn’t resolve and none of its effects occur 2. A marker placed on an object or player that modifies its characteristics or interacts with a rule or ability.)

- Create (To create a token is to put a token onto the battlefield.)

- Destroy (To move a permanent from the battlefield to its owner’s graveyard)

- Discard (To move a card from its owner’s hand to that player’s graveyard)

- Exchange (To swap two things, such as objects, sets of objects, or life totals)

- Exile (1. A zone. Exile is essentially a holding area for cards. It used to be known as the “removed-from-the-game” zone. 2. To put an object into the exile zone from whatever zone it’s currently in. An “exiled” card is one that’s been put into the exile zone.)

- Fight (When two creatures fight, each deals damage equal to its power to the other)

- Mill (To mill a number of cards, a player puts that many cards from the top of their library into their graveyard)

- Play (To play a card is to play that card as a land or cast that card as a spell, whichever is appropriate)

- Reveal (To show a card to all players for a brief time)

- Sacrifice (To move a permanent you control to its owner’s graveyard)

- Scry (To manipulate some of the cards on top of your library)

- Search (To look at all cards in a stated zone and possibly find a card that matches a given description)

- Shuffle (To randomize the cards in a deck (before a game) or library (during a game))

- Tap/Untap (To turn a permanent sideways from an upright position/To rotate a permanent back to the upright position from a sideways position)

Most Magic players know these terms by heart, and would not explain them during a game unless a novice is playing.

Evergreen Abilities

Akroma has many evergreen abilities

As promised last time, today I look at evergreen abilities (not evergreen actions; perhaps I'll cover those next time). Such abilities are described by keywords. Let's start with some terms.

'Evergreen' is a term not mentioned in the official rules, but refers to something in the game (today, abilities) that is not specific to a set or block. It is now part of the game's basic principles and thus not defined on the card itself.

Ability can mean several things in the game, but today, I'm focused on static abilities. From the rules:

604.1. Static abilities do something all the time rather than being activated or triggered. They are written as statements, and they’re simply true.

Keywords: over the years, Magic has 'keyworded' more and more abilities, most of which are static abilities. Keywords helps the veteran and cleans up the cards but can confuse the newcomer. (I look briefly at this idea here.) Some of these keywords appear only in a specific set or block: they are thematic and tied to other aspects of the expansion(s) in question. But other keywords can (and do) appear across all types of Magic releases, be they core sets, expansions, special releases, and so on. Such keywords are evergreen.

Keywords specific to a set or block are generally defined in italics on the card itself, but evergreen keywords are usually not. Consider Bridled Bighorn:

This creature has one evergreen keyword (Vigilance), presented without explanation on the card. Players are expected to know it, because it has appeared for years in various Magic products. It has an activated ability (the next paragraph), and, finally, a set-specific keyword (Saddle). That one is explained with text in italics.

Some Magic cards define evergreen keywords (generally those core sets), but not most. And sometimes, one evergreen keyword on a card will be defined, but another won't. Griffin Sentinel, below, does not define Flying but does define Vigilance. When you see such things, it generally indicates the 'age' of the keyword: older ones (Flying, here, which has had a keyword since 1993) are less likely to be defined on the card, whereas newer ones (Vigilance, here, which got a keyword in 2004) might.

To date, there are 16 evergreen keywords that are abilities on creatures, most of which are covered in section 702 of the official rules. Below, quotes from said rules are in italics.

- Deathtouch (Any nonzero amount of combat damage assigned to a creature by a source with deathtouch is considered to be lethal damage)

- Defender (A creature with defender can’t attack.)

- Double strike (this creature assigns combat damage twice; see next entry )

- First strike (modifies the rules for the combat damage step; If at least one attacking or blocking creature has first strike or double strike as the combat damage step begins, the only creatures that assign combat damage in that step are those with first strike or double strike.)

- Flash (means “You may play this card any time you could cast an instant.”)

- Flying (A creature with flying can’t be blocked except by creatures with flying and/or reach.)

- Haste (If a creature has haste, it can attack even if it hasn’t been controlled by its controller continuously since their most recent turn began.)

- Hexproof (means “This permanent can’t be the target of spells or abilities your opponents control.”)

- Indestructible (A permanent with indestructible can’t be destroyed.)

- Lifelink (Damage dealt by a source with lifelink causes that source’s controller . . . to gain that much life)

- Menace (A creature with menace can’t be blocked except by two or more creatures.)

- Protection [from ____] (A permanent or player with protection [from ____] can’t be targeted by spells with the stated quality and can’t be targeted by abilities from a source with the stated quality.)

- Reach (A creature with reach can block creatures with flying.)

- Trample (The controller of an attacking creature with trample first assigns damage to the creature(s) blocking it. Once all those blocking creatures are assigned lethal damage, any excess damage is assigned . . . to the player, planeswalker, or battle the creature is attacking)

- Vigilance (Attacking doesn’t cause creatures with vigilance to tap.)

- Ward [cost] (“Whenever this permanent becomes the target of a spell or ability an opponent controls, counter that spell or ability unless that player pays [cost].”)

Those interested in learning Magic would do well to commit the definitions of these terms to memory.

Evasion

Lu Meng, Wu General has the horsemanship evasion ability

This month I'll focus on various facets of the rules. Today: evasion abilities.

From the comprehensive rules, an evasion ability is

An ability that restricts what creatures can block an attacking creature.

Evasion abilities can be powerful and game-changing. They are mentioned in the 'declare blockers' section of the rules. After the attacker declares which of his creatures are attacking that turn, the defending player must declare blockers (if any). Part of that process:

509.1b The defending player checks each creature they control to see whether it’s affected by any restrictions (effects that say a creature can’t block, or that it can’t block unless some condition is met) . . . A restriction may be created by an evasion ability (a static ability an attacking creature has that restricts what can block it).

In essence, evasion abilities make it easier for your creatures to do damage.

The official rules mention eight evasion abilities (parentheses enclose official rules text):

- Flying (A creature with flying can’t be blocked except by creatures with flying and/or reach.)

- Intimidate (A creature with intimidate can’t be blocked except by artifact creatures and/or creatures that share a color with it.)

- Landwalk (A creature with landwalk can’t be blocked as long as the defending player controls at least one land with the specified land type . . .)

- Shadow (A creature with shadow can’t be blocked by creatures without shadow, and a creature without shadow can’t be blocked by creatures with shadow.)

- Horsemanship (A creature with horsemanship can’t be blocked by creatures without horsemanship.)

- Fear (A creature with fear can’t be blocked except by artifact creatures and/or black creatures.)

- Menace (A creature with menace can’t be blocked except by two or more creatures.)

- Skulk (A creature with skulk can’t be blocked by creatures with greater power.)

Of these, I would consider only Flying and Menace evergreen keywords (more on that term next time). The others have made their appearances but haven't been seen in standard releases for some time (though they can show up in compilation sets, Commander, and so on).

Evasion is one of those terms that is never listed on cards but you will hear mentioned by players during games or when discussing card/deck features. 

Face-Down

Stratus Dancer card art

I conclude self-proclaimed 'rules month' with a post on face-down cards. The forthcoming set, Murders at Karlov Manor, feature a keyword relevant to the topic.

Face-down cards were introduced with the 'morph' mechanic in Onslaught (2002). 'Megamorph' (Dragons of Tarkir, 2015) was similar, and now we have 'disguise' with Murders at Karlov Manor. We'll start with morph. Selections from the official rules, section 702.37:

“Morph [cost]” means “You may cast this card as a 2/2 face-down creature with no text, no name, no subtypes, and no mana cost by paying {3} rather than paying its mana cost.” 

You do *not* show the card to your opponent(s) when doing this; it is taken on trust (only cards with a morph ability can be cast face-down; rule 702.37d). So morph cards give you a choice: cast it face-up for its normal casting cost, or pay {3} and cast it face-down as a 2/2 generic creature. At a later time, whenever you have priority, you may pay the face-down card's morph cost (which is stated on the card) to turn it face-up (rule 702.37e). From the same rule:

Turning face-up "is a special action; it doesn’t use the stack." 

"Any abilities relating to the permanent entering the battlefield don’t trigger when it’s turned face up and don’t have any effect, because the permanent has already entered the battlefield." 

Megamorph is the same, but the creature gains a +1/+1 counter when it is turned face-up (see 702.37b). 

Disguise (the latest keyword) is the same, but the creature as 'ward 2' while face-down.

Four examples below on the varying costs and benefits of turning cards face-up. The general idea is that casting it face-down first will grant a later benefit.

Section 708 of the rules covers face-down spells and permanents. A lot of that section deals with the characteristics of face-down permanents (and its interactions with spells that may copy the card/etc.). Relevant portions:

708.2. Face-down spells and face-down permanents have no characteristics other than those listed by the ability or rules that allowed the spell or permanent to be face down. Any listed characteristics are the copiable values of that object’s characteristics. 

708.2a [shortened] If a face-up permanent is turned face down by a spell or ability that doesn’t list any characteristics for that object, it becomes a 2/2 face-down creature with no text, no name, no subtypes, and no mana cost.

708.3. Objects that are put onto the battlefield face down are turned face down before they enter the battlefield, so the permanent’s enters-the-battlefield abilities won’t trigger (if triggered) or have any effect (if static). 

708.4. Objects that are cast face down are turned face down before they are put onto the stack, so effects that care about the characteristics of a spell will see only the face-down spell’s characteristics. Any effects or prohibitions that would apply to casting an object with these characteristics (and not the face-up object’s characteristics) are applied to casting this object. The permanent the spell becomes will be a face-down permanent. 

708.6 [shortened]. If you control multiple face-down spells or face-down permanents, you must ensure at all times that your face-down spells and permanents can be easily differentiated from each other.  

708.11. If a face-down permanent would have an “As [this permanent] is turned face up . . .” ability after it’s turned face up, that ability is applied while that permanent is being turned face up, not afterward.

It is pretty straightforward, but warranted explanation, as it is one aspect of the game that can trip up the novice.

APNAP

Mystical Tutor card art

I mentioned Active Player, Non-Active Player (APNAP) in the last post. This post explains that concept, along with the associated concept of priority. The official rules are our starting point.

APNAP

Magic is an interactive game. It is not only about executing your strategy, but preventing your opponent(s) from doing the same. As such, there will be times when multiple players want to cast spells or activate abilities at the same time (or in response to someone else doing the same). And, there are times when triggered abilities all "go off" at the same time. APNAP is the way Magic determines the order. The basic rules here:

101.4. If multiple players would make choices and/or take actions at the same time, the active player (the player whose turn it is) makes any choices required, then the next player in turn order (usually the player seated to the active player’s left) makes any choices required, followed by the remaining nonactive players in turn order. Then the actions happen simultaneously. This rule is often referred to as the “Active Player, Nonactive Player (APNAP) order” rule.

101.4d If a choice made by a nonactive player causes the active player, or a different nonactive player earlier in the turn order, to have to make a choice, APNAP order is restarted for all outstanding choices.

Reading the other references to APNAP in the official rules, the basic point is any time things happen simultaneously, the APNAP rule decides in what order. Interestingly,

405.3. If an effect puts two or more objects on the stack at the same time, those controlled by the active player are put on lowest, followed by each other player’s objects in APNAP order (see rule 101.4). If a player controls more than one of these objects, that player chooses their relative order on the stack.

So APNAP may 'force' the active player to put their objects on the stack first [lowest], meaning they will get resolved last.

APNAP applies to all aspects of the game (there is a reason this concept is defined in the "Golden Rules" section of the document). This includes attacks:

802.4. If more than one player is being attacked, controls a planeswalker that’s being attacked, or protects a battle that’s being attacked, each defending player in APNAP order declares blockers as the declare blockers step begins. (See rule 101.4 and rule 509, “Declare Blockers Step.”) The first defending player declares all their blocks, then the second defending player, and so on.

Most of the time, order in such circumstances will not matter. But there will be occasions where it does, so understanding APNAP is important.

Priority

Related to APNAP is the concept of priority. Select rules:

117.1. Unless a spell or ability is instructing a player to take an action, which player can take actions at any given time is determined by a system of priority. The player with priority may cast spells, activate abilities, and take special actions.

117.3. Which player has priority is determined by the following rules: 

117.3a The active player receives priority at the beginning of most steps and phases, after any turnbased actions (such as drawing a card during the draw step; see rule 703) have been dealt with and abilities that trigger at the beginning of that phase or step have been put on the stack. No player receives priority during the untap step. Players usually don’t get priority during the cleanup step (see rule 514.3). 

117.3b The active player receives priority after a spell or ability (other than a mana ability) resolves. 

117.3d If a player has priority and chooses not to take any actions, that player passes. If any mana is in that player’s mana pool, they announce what mana is there. Then the next player in turn order receives priority. 

117.4. If all players pass in succession (that is, if all players pass without taking any actions in between passing), the spell or ability on top of the stack resolves or, if the stack is empty, the phase or step ends.

Summarizing, the Active Player (he/she whose turn it is) starts with priority and can take actions (cast spells, activate abilities, etc.). When they are done, they pass priority to the Non-Active Player on their left. When he/she takes actions and then passes, priority goes to the next Non-Active Player, and so on, and until everyone passes. Then the objects on the stack resolve. And, per 117.3b, as things resolve on the stack, the active player has a chance to 'react' at each point if they so choose. In thoses cases,

117.7. If a player with priority casts a spell or activates an activated ability while another spell or ability is already on the stack, the new spell or ability has been cast or activated “in response to” the earlier spell or ability. The new spell or ability will resolve first. See rule 608, “Resolving Spells and Abilities.”

Two-player Magic games rarely get into APNAP/priority weirdness, but for multiplayer games, it can get messy. Knowing these rules can help disentangle things.

The Stack

Fblthp, the Lost card art

I have mentioned the stack several times in this blog, but never explained it. I do so today.

Magic's official rules describe this concept in detail. The word is used 416 times in that document, showing its importance. Some basics, quoted or paraphrased from the rules:

The stack is a zone. A zone is a place where objects can be during a game. There are "seven zones in Magic: library, hand, battlefield, graveyard, stack, exile, and command. Each player has their own library, hand, and graveyard. The other zones are shared by all players." (Rule 400.1)

Section 405 focuses on the stack. Relevant portions from that section:

405.1. When a spell is cast, the physical card is put on the stack. When an ability is activated or triggers, it goes on top of the stack without any card associated with it. 

405.2. The stack keeps track of the order that spells and/or abilities were added to it. Each time an object is put on the stack, it’s put on top of all objects already there. 

405.3. If an effect puts two or more objects on the stack at the same time, those controlled by the active player are put on lowest, followed by each other player’s objects in APNAP order. If a player controls more than one of these objects, that player chooses their relative order on the stack. 

405.5. When all players pass in succession, the top (last-added) spell or ability on the stack resolves. If the stack is empty when all players pass, the current step or phase ends and the next begins.

Note: "APNAP order" above means "Active Player, Non-Active Player." The active player is whose turn it is; the non-active players go in turn order [clockwise] from that player. I'll cover that another time.

Spells and activated/triggered abilities remain on the stack until they are resolved, countered, or otherwise leave the stack (see rules 112 and 113). 

Summarizing, the stack is a "first in, last out" concept where players stack spells and abilities until everyone has passed. Then the topmost spell/ability is resolved, then the next, and so on until the stack is empty. The stack exists in all steps/phases of the game. In a given phase, the active player has priority to put something on the stack first; if they pass, then the non-active players can choose to do the same. If they pass, then the game proceeds to the next phase.

Two things to note:

1) Most counterspells in the game counter spells. Note that "Activated and triggered abilities on the stack aren’t spells, and therefore can’t be countered by anything that counters only spells. Activated and triggered abilities on the stack can be countered by effects that specifically counter abilities. Static abilities don’t use the stack and thus can’t be countered at all." (Rule 113.9)

2) Some things that happen during the game don’t use the stack (405.6). Summarizing this section, these are:

- effects (the result of spells and abilities resolving)

- mana abilities (I cover this in a different post)

- special actions (rule 116)

- turn-based and state-based actions (see rule 703 and 704)

- a player conceding the game [this one is hilarious. Imagine if "I concede" would go on the stack, and someone else could counter it. "No you don't. Sit down."]

Example 1:

The simplest (and most common) example are two spells. I cast Hurloon Minotaur; that goes on the stack. My opponent casts Cancel; that goes on top of the stack. 

I have a chance to respond but pass; my opponent passes, too. Then the spells on the stack are resolved top to bottom: Cancel resolves, targeting Hurloon Minotaur. My minotaur spell is canceled and goes to my graveyard [sob].

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Example 2:

Order matters greatly. Here, I have a Grizzly Bears on the battlefield and declare it as an attacker, tapping it to do so. I pass priority and my opponent casts Cut Down targeting it. I have priority again. In response, I cast Giant Growth. To the stack is (top to bottom) Giant Growth, Cut Down.

Everyone passes. Giant Growth resolves, making the Grizzly Bears 5/5 until end of turn. Cut Down then resolves, but has no target, because Grizzly Bears now have a total power and toughness greater than 5. The spell 'fizzles' and nothing happens (it goes to the graveyard). Grizzly Bears attacks as a 5/5.

Now let's reverse the order. I attack with my Grizzly Bears, and (having priority) choose to cast Giant Growth right away. My opponent, in response, casts Cut Down. Now the stack is (top to bottom) Cut Down, Giant Growth. Everyone passes. Cut Down resolves, and the Grizzly Bears is destroyed (and put in the graveyard). Giant Growth then resolves, but has no target, because Grizzly Bears is no longer there. The spell 'fizzles' and nothing happens (it goes to the graveyard). There is no attack.

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In these simple examples, the stack is straightforward. But things can get complicated quickly, especially when you throw abilities and multiple players into the mix. 

Seasoned Magic players don't say "I put [x] on the stack." They'll say, instead, something like "I play Hurloon Minotaur" and expect that anyone who wants to respond will speak up ("in response, I ___") and do so at that time. If nobody does, it resolves and enters the battlefield.

The stack is important to understand, even if it goes unmentioned in most Magic games. It is a key part of the game's strategy, enabling the interactions that make the game so exciting, challenging, and fun.