The scenario is Gitrog Monster vs Decimate. The question is, do the controller of both Gitrog and the land draw a card?

608.2c The controller of the spell or ability follows its instructions in the order written.

Now, the same way Putrefy is not a modal spell*. I read Decimate as not a series of instructions, but rather as one instruction which complexity is due to different card types are being chosen. To me it is like Innocent Blood, but with different types of cards affected.

Question 1:
Is my interpretation correct, and thus does the Gitrog trigger?

Question 2:
Is there any clear ruling of when it is a series of instructions and when it is not? For special abilities like Entwine and modal spells with multiple choices (Cryptic Command) it is clear. As is the case with Serum Visions where the two effects are distinguished by a dot. Is it safe to say that you need a dot or semi-colon to make it two different instructions?

Edit: Clarification - Player A Controls both the land being destroyed by decimate, and the Gitrog Monster which is also destroyed by Decimate. If they are destroyed at the same time gitrog will trigger. If not, the Gitrog is destroyed first and can of course not trigger when the land is destroyed “later” in the resolve of Decimate. But what distinguishes between being the same effect and being a series of effects? Most likely some punctuation rules. Where are these defined?

*:If e.g. Mirrage Mirror is targeted and in response becomes a copy of a creature, it will still be destroyed as it is still a legal target (subset of “creature or artifact”).

Edited Olle Liljefeldt (Oct. 2, 2017 05:24:06 AM)

Unless the card establishes explicit timing on its own, the rules say that the action is performed sequentially (such as drawing multiple cards), or the like, the actions described by any one verb are simultaneous with each other. As such, Decimate destroys all of its targets simultaneously. However, if The Gitrog Monster and one of your lands are both destroyed by Decimate, The Gitrog Monster will not trigger–not because of how Decimate works, but because of how The Gitrog Monster itself works.

Section 603 in the Comprehensive Rules contains the rules for handling triggered abilities; the relevant part here are 603.10 and 603.3c. The former tells us how the game knows which triggered abilities trigger off of any given event: the normal procedure is that immediately after something (anything) happens, the game looks around to see if any abilities exist that A) are functioning and B) want to trigger off of that event.

However, this normal procedure doesn't work for every type of trigger. We'll use Black Cat as an example–let's say that a Black Cat dies. Under the normal procedure for triggered abilities, the game would examine the game state after the Cat is in the graveyard to see if anything should trigger, and see that there's a Black Cat in the graveyard that just died…but its ability wouldn't be functional at this point, because unless the card says otherwise (and it doesn't), the abilities of a permanent card don't function while it's in the graveyard. So nothing would trigger. That…obviously, doesn't work.

To get around this, the rules say that certain types of triggers “look back in time” to how things were before whatever happened–these abilities trigger if they A) were functioning *immediately before* the event, and B) want to trigger off of it. Leaves-the-battlefield abilities (like Black Cat) are the largest and most common examples of such abilities. So in our example scenario, Black Cat triggers because the Cat was on the battlefield (and therefore its ability was functioning) immediately before the triggering event. This is why leaves-the-battlefield abilities can “see” other permanents that are leaving at the same time as the card they're on.

And this is why The Gitrog Monster doesn't trigger off of a Decimate that destroys both it and a land: because its card-drawing ability is not a leaves-the-battlefield ability, since abilities that trigger off of cards entering a specific zone “from anywhere” are explicitly defined as not being leaves-the-battlefield abilities in 603.6c. As the ability is not a leaves-the-battlefield ability (and doesn't fall under any of the other exceptions listed in 603.10), it doesn't “look back in time”, so it cannot “see” other permanents that are being put into the graveyard at the same time as the Monster itself.

(If you replaced The Gitrog Monster with a card with a leaves-the-battlefield ability, such as Titania, Protector of Argoth, that card will trigger off of being destroyed by Decimate at the same time as a land.)

Edited Callum Milne (Oct. 5, 2017 04:08:53 PM)