You don't get a meld trigger during that turn. For that to occur, both Bruna and Gisela must both be on the battlefield when the end step begins. But Gisela is still in exile, until the delayed trigger from the Interlude returns her. So yes, your friends were correct for the reasons they stated.
APNAP mostly applies to putting triggers on the stack at the same time. But Gisela's meld trigger doesn't fire because its condition isn't met (she's not even on the battlefield at that time), so it is never put on the stack in the first place.
Are there any problems with temporarily turning panharmonicon into a creature - with Sydri, Galvanic Genius for instance - to make it easier to copy with clone effects or a kicked Rite of Replication? My understanding is the copies will simply become artifacts at the end of the turn.
Copies made of a usually noncreature permanent, that has temporarily been made a creature by an effect created by a resolvng spell/ability, will enter the battlefield as a noncreature permanent. The animation effect on the original is not copied.
Well, say you cast a spell from your hand. Up to three triggers go on the stack, which are put there in APNAP order (active player non active player). So it matters who controls the three permanents, because the controller of the permanent is also the controller of the trigger. A player who controls more than one can choose their relative order on the stack.
Knowledge Pool and Possibility Storm can only trigger from the original spell, and only if it is cast from the hand. The spells they allow to cast can only trigger Hive Mind. Hive Mind's copies aren't cast, so they don't trigger anything. So at most, you get three Hive Mind triggers to copy a spell for each player (the original spell, a spell out of the Pool, and a spell from PStorm). You will not resolve your original spell, because it gets exiled by the Pool or send to the library by PStorm. The other players will each get a copy of that original spell if it is an instant or sorcery. You get a spell out of the Pool, and a spell from PStorm, while everyone else will get a copy of those spells, if they are instants/sorceries.
Casting a sorcery at another time other than with sorcery timing (during your main phase, when the stack is empty, and you have priority) is an illegal action, unless something (like a resolving spell/ability) grants you special permission. If that mistake is caught fairly quickly, then the game can be rewound to right before the illegal acton was taken. So in that case, the card returns to your hand, all permanents that were tapped for mana to cast it are untapped, etc. (Though there are a few rare things that cannot be reversed!) Note, that the entire game is rewound to that moment, all actions taken after that time are nullified! If the error is caught only after significant game decisions have been made afterwards, then the game state will likely stay at is is, and you just play along. During a tournament, the judge will make that call. Though you and your opponent will get a penalty (a Warning, though if it is a repeated offense, the penalty can be much harsher, up to a disqualification for cheating if the judge deems it intentional). In a casual game, it's really up to all players for how to handle the situation.
No. A CDA is an ability that describes the value of a characteristic normally found somewhere else on the card (usually because there isn't enough space and so the nessessary text is put into the text box). Transforming an object simply changes its set of characteristics from the front side to the back side and vice versa. But this is not due to a static ability.
604.3. Some static abilities are characteristic-defining abilities. A characteristic-defining ability
conveys information about an object’s characteristics that would normally be found elsewhere on
that object (such as in its mana cost, type line, or power/toughness box) or overrides information
found elsewhere on that object. Characteristic-defining abilities function in all zones. They also
function outside the game.
Ormendahl doesn't have a CDA (characteristic defining ability), he simply has a printed power/toughness. It would "apply" before even copy effects (layer 1) have their chance. So copy effects would already overwrite it.
Yes, aura spells on the stack target. However, in this case, the aura doesn't go to the stack at all. The trigger from Matter Reshaper puts it directly from the library onto the battlefield. The only thing on the stack here is that trigger. When an aura enters the battlefield without having been an aura spell on the stack, you attach it to a valid object/player. This gets around shroud and hexproof, since you don't target the object/player. But protection will still interfere, since that ability also explicitly forbids to enchant.
If you somehow can't attach the aura to a legal object/player, it remains in its previous zone. Unless that zone is the stack (like if a resolving Copy Enchantment copies an aura on the field without having something to attach to), in that case, the card is put into the graveyard.
When determining an objects characteristis, you start with what's printed on the card. So in the case of a DFC creature, your start with the printed value for power/toughness of whichever side is up, and apply any changes to that over it in a series of layers. Timestamps only factor in within those layers, but the printed value is always first, before you even get to any layers.
When you transform the Abbey, the counters from awaken remain on the creature it becomes. The animation effect of awaken is still present, but since the transfromed side of the Abbey is already a creature, that becomes irrelevant. Unless the permanent transformes back somehow, in which case, it stays a creature, because of that effect (It'll be a 3/3 again, a 0/0 with 3 +1/+1 counters). With awaken 3, Ormendahl, Profane Prince will be a 12/10 creature due to those +1/+1 counters.
EDIT:
Sorry, got this wrong. Since awaken says it becomes a 0/0 creature, this will overwrite Ormendahl's power/toughness, so the creature is still a 3/3 due to the counters. Ormendahl will also be a Demon Elemental.
Yes, the Diamond will be a 3/3 creature (0/0 with 3 +1/+1 counters). Awaken only cares about the target being a land when you cast the spell, and when it resolves. Once the animation effect is in place, removing the effect that made it a land doesn't make that animation effect invalid. And since awaken uses the clause "it's still a land", the permanent keeps its types. So while it isn't a land anymore, it is sill an artifact. Removing the Song makes the permanent from a land creature (Song does overwrite previous types!) into an artifact creature.
When the first ability (the copy) resolves, you may choose to cast one of those cards. It's put on the stack, eventually resolves and goes to the graveyard, then the second instance of the ability resolves, allowing you to cast the other card. If you do, it goes on the stack as a spell, eventually resolves and goes to the graveyard. If you chose not to cast a card the first time around, you have two cards to choose from for this second instance.
1) Yes. The Helm's rules text itself tells you so: "You may choose not to untap Helm of Possession during your untap step." This statement only applies to the Helm, not any other permanents under your control. So your choice to untap it or not does not affect those other permanents in any way. If nothing is keeping them tapped, you have to untap them.
2) The removed creature goes to its owner's graveyard. Nothing happens to the artifact that gained you control of the creature at that time, it remains as it was right before. You may still choose to not untap the artifact during your untap step, but doing so will likely not gain you any advantage.
Yes. The exile trigger is only looking for the token created by the spell/ability. It's only looking for that specific token.
It would be different if something like Doubling Season was involved, since it only creates a replacement effect changing the number of tokens created. But it is still the original spell/ability creating the tokens, so the delayed trigger will exile all of them.
Yes, the token will trigger its own ability, since it is an artifact and it entered the battlefield. ETB trigger conditions are checked after the event of a permanent entering the battlefield, and that check includes all newcomers. So your opponent is pinged for two damage total.
Also, yes, the damage can be redirected to the opponent's planeswalkers. It is noncombat damage dealt by a source you control to an opponent, so the planeswalker damage redirection rule can be applied.
APNAP mostly applies to putting triggers on the stack at the same time. But Gisela's meld trigger doesn't fire because its condition isn't met (she's not even on the battlefield at that time), so it is never put on the stack in the first place.
Copies made of a usually noncreature permanent, that has temporarily been made a creature by an effect created by a resolvng spell/ability, will enter the battlefield as a noncreature permanent. The animation effect on the original is not copied.
Knowledge Pool and Possibility Storm can only trigger from the original spell, and only if it is cast from the hand. The spells they allow to cast can only trigger Hive Mind. Hive Mind's copies aren't cast, so they don't trigger anything. So at most, you get three Hive Mind triggers to copy a spell for each player (the original spell, a spell out of the Pool, and a spell from PStorm). You will not resolve your original spell, because it gets exiled by the Pool or send to the library by PStorm. The other players will each get a copy of that original spell if it is an instant or sorcery. You get a spell out of the Pool, and a spell from PStorm, while everyone else will get a copy of those spells, if they are instants/sorceries.
604.3. Some static abilities are characteristic-defining abilities. A characteristic-defining ability
conveys information about an object’s characteristics that would normally be found elsewhere on
that object (such as in its mana cost, type line, or power/toughness box) or overrides information
found elsewhere on that object. Characteristic-defining abilities function in all zones. They also
function outside the game.
If you somehow can't attach the aura to a legal object/player, it remains in its previous zone. Unless that zone is the stack (like if a resolving Copy Enchantment copies an aura on the field without having something to attach to), in that case, the card is put into the graveyard.
With awaken 3, Ormendahl, Profane Prince will be a 12/10 creature due to those +1/+1 counters.EDIT:
Sorry, got this wrong. Since awaken says it becomes a 0/0 creature, this will overwrite Ormendahl's power/toughness, so the creature is still a 3/3 due to the counters. Ormendahl will also be a Demon Elemental.
Yes, the Diamond will be a 3/3 creature (0/0 with 3 +1/+1 counters). Awaken only cares about the target being a land when you cast the spell, and when it resolves. Once the animation effect is in place, removing the effect that made it a land doesn't make that animation effect invalid. And since awaken uses the clause "it's still a land", the permanent keeps its types. So while it isn't a land anymore, it is sill an artifact. Removing the Song makes the permanent from a land creature (Song does overwrite previous types!) into an artifact creature.
2) The removed creature goes to its owner's graveyard. Nothing happens to the artifact that gained you control of the creature at that time, it remains as it was right before. You may still choose to not untap the artifact during your untap step, but doing so will likely not gain you any advantage.
It would be different if something like Doubling Season was involved, since it only creates a replacement effect changing the number of tokens created. But it is still the original spell/ability creating the tokens, so the delayed trigger will exile all of them.
Also, yes, the damage can be redirected to the opponent's planeswalkers. It is noncombat damage dealt by a source you control to an opponent, so the planeswalker damage redirection rule can be applied.