Good morning, Happy New Year, and welcome back to the Rules Tips Blog! We hope you all had a lovely holiday, and we now resume your regularly (ish) scheduled Rules Tips content.
Today we’re going to be talking a bit about State-Based Actions. SBAs, as they are frequently called, are sort of the janitors of the game. There’s a list of 22 of them, though some are a bit esoteric (Two of them are for variant casual formats, one is for Commander, and two are for Two-Headed Giant!); the important thing to know is that they’re constantly watching for certain conditions, and then kicking in to do their thing. SBAs are checked and enacted immediately before a player gets priority, every single time a player would get priority. They’re also re-checked immediately afterwards, if they actually changed anything.
That’s a pretty dense set of ideas, so let’s have some examples. “If a creature has damage greater than its toughness marked on it, that creature is destroyed” is a State-Based Action- this is the mechanism that actually kills your creature when they get a Shock thrown at them. But let’s say you have a Merfolk Mistbinder and a bunch of 2/2 Merfolk, who are now 3/3 thanks to the Mistbinder. Your opponent decides to throw down a Fiery Cannonade to deal with that situation. It resolves, and SBAs take a look at the board: A bunch of 3/3s with 2 damage they don’t care about. But a 2/2 with 2 damage needs to be destroyed, so they destroy it. And since SBAs changed something, they re-check to see if anything else needs to be dealt with now- and hey, what do you know, suddenly there’s a bunch MORE 2/2s with 2 damage on them, now that Mistbinder isn’t buffing them. So all those get wiped out too, with no chance to do anything between Mistbinder dying and the rest dying.
And that ‘no chance’ includes triggers. Anything that cared about Mistbinder dying, or about being dealt damage, won’t have the trigger put onto the stack until the SBAs are done doing their thing. So how about another example? You’ve got three Carnage Tyrants on board because you never learned the meaning of the word “overcommitting”, and you’re at 3 life. Your opponent has three Sun-Crowned Hunters, and is at 6 life. You attack all out, your opponent puts one Hunter in front of each Carny T… and then they lose. Your Carnage Tyrants are gonna smack the Hunters for 4 and your opponent for 3, simultaneously. That triggers all three of the Hunters, but first our old pals the State-Based Actions look in on things, and they see a player at -3 life. That player is removed from the game immediately, leaving you as the winner, before those triggers even touch the stack, let alone resolve. Because no matter how quick you think you may be- you’re not quicker than SBAs.
Today’s Rules Tip was written by Trevor Nunez