Standard FNM.

AP has Deathmisth Raptor in GY. AP megamorphs Den Protector and says trigger, pointing to Den Protector. NAP says in response and casts Hallowed Moonlight. AP says ok, then says trigger pointing to Deathmist. They call me over.

How would you talk them through this?

Hallowed moonlight is obviously being cast in response to Den Protector's
trigger, since that is the only legal time it can be cast. Assuming I don't
think AP is intentionally being misleading, then Hallowed Moonlight will
resolve, and then Den Protector's trigger will resolve, returning Deathmist
Raptor to AP's hand. Explain what Megamorph is and walk them through
resolving the stack if necessary.

If Hallowed Moonlight is being cast in response to Den Protector's trigger,
then we have a problem, as Den Protector requires a target to be chosen.
We should be backing up the casting of Hallowed Moonlight and asking AP for
a target for his trigger, then allowing NAP to respond as they wish.

To follow up with what Justin said -
Both the target for Den Protector's ability and Deathmists' Reanimate trigger are added to the stack at the same time, in the order that AP choses. When Den Protector's trigger goes on the stack, it must have a target.

There is some OOOS going on here, and I would explain that to the players so that both have a better understanding of why this situation has become unclear. Then back up the play to the DP's megamorph, having him declare a target for DP and announce Deathmist's trigger.

NAP can chose to play Hallowed Moonlight if he wants, but it's worth noting that Deathmist Raptor's trigger is a may ability, and AP can chose to leave it in the GY if they want. If AP chooses to resolve the Raptor's trigger and exile the Raptor, I would not interfere. I would explain the play mistake after the round has completed so that the player has better understanding of how their cards work.

OoOS exactly what i did, btw. I also explained that this isn't a game of ‘Gotcha’ and that it was FNM not Comp REL as one player is super competitive. Then i asked the AP why he thinks his opponent is playing that card now. He said that he probably wants to stop Deathmist from entering back in. I agreed with that assessment. Finally i told them to talk about it with each other to see if they could get onto common ground. It took all of 3 seconds to come to an agreement and Deathmist stayed where it was.


But as always, i was interested in hearing other POV.

Thank you.

For what it's worth, Darren, I think your solution is appropriate at Competitive as well. Magic: the Gotcha is a thing we try to discourage in any environment, where possible.

I mean, that's basically the reason OOOS exists.

I would investigate for cheating. If it seems to be a misunderstanding of how triggers go onto the stack I'd explain it to them.

the stack is currently

Hallowed Moonlight
Deathmist Raptor
Den Protector

Regardless of his wishes, Den protectors megamorph trigger and Deathmist zone change trigger, triggered off the same event, and were put onto the stack at the same time. You cant stick hallowed moonlight between them, or annouce a trigger after the fact as a way to move it up the stack.

Wait, how does Hallowed Moonlight end up between the two triggers? They are put onto the stack at the same time.