#state-based actions

[magicjudge]

I have a question about Wall of Roots and when exactly it dies while paying costs. Suppose I have four -0/-1 counters on my Wall of Roots but haven't yet activated it this turn. I go to cast Eldritch Evolution, and activate Wall of Roots to pay G. Wall of Roots is now a 0/0. Does it die immediately in the middle of paying costs? Or can I still sacrifice it to Eldritch Evolution's additional cost?

I know that this wouldn't work with something like Wild Cantor, which puts itself into the graveyard as part of its mana ability. But I'm not sure about a case like this where the creature would die due to state-based effects in the middle of paying costs.

You can do this so long as you're putting that fifth -0/-1 counter on it during the process of casting the spell.

When you're casting a spell, you get the chance to generate mana to pay for that spell's costs before you have to pay them. This means that you can activate Wall of Roots and reduce it to 0/0 before you need to pay 1GG or sacrifice a creature.

You're also able to sacrifice Wall of Roots to pay that cost because state-based actions are never checked in the middle of casting a spell, so the fact that Wall of Roots is 0/0 won't matter until after the casting process is complete, at which point it has been sacrificed already.

[magicjudge]

If Zilortha is dealt 2 damage during the turn, can it be killed with a -1/-1 effect?

First of all, contrary to what Arena shows you, normal damage doesn't reduce toughness. Zilortha still has 3 toughness even when it has taken 2 damage, so reducing its toughness to 2 won't do anything thanks to its ability. Giving it -3/-3 would kill it, however, since dying to 0 toughness is a different state-based action than dying to lethal damage.

Zilortha's ability causes you to compare marked damage to a creature's power rather than its toughness, so Zilortha would die if it had 7 damage marked on it. (Creatures with 0 power won't die unless they have at least 1 damage marked on them, though. Lethal damage is only checked if there is some amount of damage marked on a creature.)

[magicjudge]

In response to your Emporer Crocodile response. I had thought state based things like it's ability don't get checked in the middle of a resolution? Like how being wheeled wouldn't kill your Psychosis Crawler right?

Or am I missing a difference between those two interactions?

You're thinking of state-based actions which are only checked before a player gets priority. State triggers are a totally different thing.

A state trigger is always looking for its thing to happen, but a state-based action only checks at certain times.

[magicjudge]

My opponent has Cloudsteel Kirin equipped to a creature and is at -1 life, and I cast Chaos Warp targeting their creature, assuming the Chaos Warp resolves as intended, do they immediately lose or is there a possibility for the revealed permanent to restore them to a positive life total and prevent that? Bonus detail, does that card being a commander redirected to the command zone change that?

Chaos Warp will fully resolve before your opponent loses the game. They would have to hit Platinum Angel or another card that prevents or replaces losing the game in order to stay alive, though. One that just gained them some life as a trigger wouldn't work because they would die before the trigger went on the stack. And no, a commander going to the command zone doesn't change anything here. Losing the game for having 0 or less life is a state-based action and state-based action are only checked immediately before a player would receive priority. They're never checked in the middle of the resolution of a spell or ability.

[magicjudge]

Does Geth, Thane of Contracts' replacement effect make it so that if it reanimated your commander you couldn't put it back in your command zone when it dies again?

No, your commander can go back to the command zone just fine.

When your commander goes to the graveyard or exile, it goes to those zones and then you get the option to move it to the command zone the next time state-based actions are checked.

Moving to the command zone is only a replacement effect if your commander would move to your hand or library, and that replacement effect has the special quality of being able to modify an event any number of times, i.e. you can always do it no matter what other replacement effects might apply.

[magicjudge]

If I’m using Lazav 1.0 and Murder to kill my opponent’s Kokusho commander, if they trigger Kokusho’s death trigger can Lazav become a copy of it?

Yes.

Lazav's ability doesn't target anything and doesn't have to do anything to the card that triggered it, so even after your opponent moves Kokusho back to their command zone from the graveyard, Lazav's trigger still saw Kokusho for the time it was in the graveyard and will use its last known information when determining how to copy it if you choose to do so.

[magicjudge]

If I cast a rite of replication on an Elish norn and my opponent has a four base 4 toughness creature, do I chose the order of SBA so that their creatures die before I sac my EN to the legend rule??

As I explained in my last answer about state-based actions, they're all processed and applied at once with none happening before any others.

This means that your spare Cenobite is put into the graveyard at the same time as any of your opponents creatures that would die from the -4/-4 debuff.

[magicjudge]

If I play a Storm Herald and get back Imprisoned in the Moon and something that grants protection from blue (lets say Blue Ward), which falls off first? Does not being a creature mean the creature aura falls off, or does protection from blue mean the blue aura falls off?

They both fall off at the same time.

When state-based actions are checked, everything that needs to be done by them is noted and then all of those things happen simultaneously. No state-based action takes priority over any other.

In the example you cite, Imprisoned in the Moon is illegally attached to Storm Herald because Blue Ward is giving Storm Herald protection from blue while Blue Ward is illegally attached because Imprisoned in the Moon makes Storm Herald no longer a creature. An illegally attached aura goes to its owner's graveyard when state-based actions occur, and so both Auras would be put into your graveyard. However, Storm Herald's replacement effect causes them to be exiled instead.