This page is current as of Comprehensive Rules October 2010. Please direct your feedback to: The Staff

State-based actions can be compared to the plumbings we have in our houses: we don't see them, and we don't want to see them; however, we need them to dispose of exhausted water.

This is what state-based actions mainly do: watch over the game to spot stuff that needs to be cleared up, and they dispose of it. The game only checks if any state-based actions need to be performed at very specific times:

• Immediately before a player receives priority
• As the cleanup step begins

If at least one state-based action occurs, the game checks again if other state-based actions are applicable. As soon as all checks are false, the game proceeds. During the cleanup step, players only receive priority if a state-based action occurs or a triggered ability goes on the stack, otherwise the turn ends.

Example. I control Scion of Oona, Pestermite (currently 3/2) enchanted with Curiosity, and Briarberry Cohort (currently 3/3), and my opponent casts Hurricane with X=1. After Hurricane has resolved, the game checks if there's some state-based action to perform, and sees that Scion of Oona has lethal damage on it. Scion of Oona is destroyed, and another check is performed. Pestermite has now shrunk to a 2/1, and still has 1 damage marked on it, so it's destroyed as well. Since this check was positive, another is in order. Now Briarberry Cohort is a 1/1, since I don't control any other blue creature, with 1 damage on it, and Curiosity is not attached to anything: so Briarberry Cohort is destroyed and Curiosity is put into its owner graveyard. These two actions happen simultaneously, so I get to choose the order Briarberry Cohort and Curiosity will end up in my graveyard. In the end, I'll have Scion of Oona on the bottom of my graveyard, Pestermite on top of it, and then Briarberry Cohort and Curiosity in the order I chose. Even though no cards dependent on the order of the graveyard have been printed since Urza's Saga, older cards used to reference the card on "top" or "bottom" of the graveyard quite frequently, as seen for example in Phyrexian Furnace, Bösium Strip and many more.

Scion of Oona

All the state-based actions are defined within the rules; cards can't introduce new state-based actions. ^[1] Here is a list of all the state-based actions, grouped for convenience:

• Waving goodbye to dead players:
  • A player with 0 or less life loses the game. [CR 704.5a]
  • A player that tried to draw from an empty library loses the game. [CR 704.5b]
  • A player with ten or more poison counters loses the game. [CR 704.5c]

• Burying corpses:
  • Creatures with toughness 0 or less are put into their owners' graveyard. [CR 704.5f]
  • Creatures with lethal damage^[2] on them are destroyed. [CR 704.5g]
  • Creatures damaged by a source with deathtouch are destroyed.^[3] [CR 704.5h]
  • Planeswalkers with loyalty 0 are put into their owners' graveyard. [CR 704.5i]

• Tearing tokens apart:
  • Tokens that are not on the battlefield or are phased out cease to exist. [CR 704.5d]
  • Copies of spells that are not on the stack cease to exist. [CR 704.5e]
  • Copies of cards that are neither on the stack nor on the battlefield cease to exist. [CR 704.5e]

• Unique stuff is unique:
  • If two or more planeswalkers with the same subtype are on the battlefield, they're all put into their owners' graveyards. [CR 704.5j]
  • If two or more legendary permanents with the same name are on the battlefield, they're all put into their owners' graveyards. ^[4] [CR 704.5k]
  • If two or more permanents with the supertype world are on the battlefield, all except the most recent^[5] one are put into their owners' graveyards. If there is a tie, they're all put into their owners' graveyards. [CR 704.5m]

• Weapons and enchantments:
  • If an Aura is attached to an illegal object or player, or is not attached at all, it's put into its owner graveyard. [CR 704.5n]
  • If an Equipment or Fortification is attached to an illegal permanent, it becomes unattached from it and remains on the battlefield. [CR 704.5p]
  • If a creature is attached to an object or player^[6], it becomes unattached and remains on the battlefield. [CR 704.5q]
  • If a permanent that's neither an Aura, an Equipment, nor a Fortification is attached to an object or player, it becomes unattached and remains on the battlefield. [CR 704.5q]

• Counting counters:
  • +1/+1 counters and -1/-1 counters on the same permanent annihilate each other. ^[7] [CR 704.5r]
  • If a permanent has an ability that says it can't have more than N counters of a certain kind on it, but there are more than N counters of that kind on it, all but N of those counters are removed from it. [CR 704.5s]

• Variant games:
  • In a Two-Headed Giant game, a team with 0 or less life loses the game. [CR 704.5t]
  • In an EDH game, a player that's been dealt 21 or more combat damage by the same general over the course of the game loses the game. [CR 704.5u]
  • In an Archenemy game, a non-ongoing schame whose triggered ability has resolved is turned face down and put on the bottom of its owner's scheme deck. ^[8] [CR 704.5v]

Note: Almost all of the state-based actions that move stuff to the graveyard do so without destroying it, so regeneration can't replace this event and abilities that trigger "when [something] is destroyed" don't trigger. However, creatures with lethal damage and creatures with deathtouch damage are destroyed, so regeneration can save them. Some permanents are indestructible. This means that when we check if state-based actions apply, lethal damage and deathtouch damage are ignored on them. The game doesn't try to destroy them and fail; it doesn't even try. [9]

All these actions check if something is true right now, except two: a player loses if it was unable to draw and a creature is destroyed if it was dealt damage from a source with deathtouch. We've omitted it for legibility's sake, but these actions only check if the appropriate event has happened since the last time state-based actions were checked.

Example. Let's say a player controls a Platinum Angel and begins the turn with an empty library. He would lose the game during the draw step, but the Angel prevents it, so he keeps playing he enters his main phase and casts Rite of Consumption, sacrificing Platinum Angel to it. Now he's not protected by it any more, but even though he tried to draw from an empty library earlier, this didn't happen since the last time state-based actions were checked (that is, when he received priority as his main phase begun), so state-based actions don't try to kill him.

Platinum Angel

State-based effects are not controlled by any player.

Example. I control a Sacred Ground, and my opponents Lightning Bolts my animated Treetop Village. The Bolt deals 3 damage to it, then state-based actions destroy it. It was not destroyed by a spell controlled by my opponent (it only dealt damage to it, but state-based actions actually destroyed it), so Sacred Ground doesn't trigger.

Sacred Ground

There are some triggered abilities that trigger when the state of the game matches a condition: there are called state-triggered abilities, and follow the rules for triggered abilities, with some addition. State-based actions and state-triggered abilities should not be mixed up:

• State-based actions only occur at the times specified above. If one of their conditions is met at any other time, they ignore it. When they are to happen, they happen immediately, without using the stack.
• State-triggered abilities monitor the relevant game state at any time, and will always trigger if it's met. However, they use the stack as all abilities do, and can be responded to.

Example. I control Ancient Ooze and Emperor Crocodile, and cast Victimize targeting a couple of creatures in my graveyard. If I sacrifice the Crocodile while I resolve Victimize, the Ooze will temporarily drop to a 0/0, then go back to positive toughness as the two target creature cards return to the battlefield. Since state-based actions are not checked during the resolution of a spell, but only as a player would get priority (that is, after the spell is done resolving), the Ooze will stay alive. On the other hand, if I sacrifice Ancient Ooze, Emperor Crocodile's ability will detect that it's the only creature I control, and trigger. After the spell has resolved, it will be put onto the stack as I receive priority, even though I now control two other creatures, and force me to sacrifice the Crocodile.

Emperor Crocodile Ancient Ooze

All applicable state-based actions are performed simultaneously, regardless of the order of the actions that happened before. If this causes the same action to occur more than once, all these occurrences are consolidated into one, so it only needs to be replaced once. For the purpose of applying triggered abilities, the game sees a transition from the state before state-based actions were applied to the state after all have been applied - no partial state exists.

Example. Greater Basilisk is blocked by Gorilla Chieftain. After damage is assigned, two state-based actions occur: lethal damage and deathtouch damage both try to destroy Gorilla Chieftain. The two occurrences of the same action are consolidated into one, and only one regeneration shield is enough to save the Ape.

Gorilla Chieftain Greater Basilisk

Example. My Dusk Urchins, which has a +1/+1 counter on it, is blocking Smoldering Butcher. When damage is dealt, four -1/-1 counters are put on Dusk Urchins. Two state-based actions apply: the +1/+1 counter vanishes with one of the -1/-1 counters, and Dusk Urchins is put into my graveyard because it has toughness 0. Both actions are performed; however, the game sees Dusk Urchins on the battlefield with four -1/-1 counters and one +1/+1 counter on it before the event, and Dusk Urchins in the graveyard afterwards. I will draw four cards.

Dusk Urchins

Footnotes