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[CMM] Pearl Medallion
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Instructions very confusing on this one. Without knowing the mechanic, I would be very confused as to how to play this. It seems to be pick a side, play it, then later turn you can pay to unlock the other side. But why the reminder "that door unlocks"?
I looked up the rules, and holy shit is it confusing when you get into detail.
You cast an Enchantment with a Room subtype and pay for either side. You ignore the other side.
If the Room has one side unlocked, you may unlock the other by paying the cost of the other side. This doesn't use the stack, and can't be responded to. Triggers that occur because of this can be responded to.
If the Room has neither side unlocked (maybe it got put into the battlefield with Open the Vaults or it got blinked), you can only open a side at sorcery speed, regardless of what was said in the bullet point above.
The mana value of a Room is equal to the unlocked doors. This room can have a mana value of 0, 2, 6, or 8, depending on what's unlocked.
If you copy a Room, you copy what is and isn't unlocked.
Functionally, it's not bad, but the corner cases these cards have is crazy.
I got the basics of the mechanic pretty easily, but the last 2 are really confusing and not what I would have expected
Soooooo it has a mana value of 0 while in my hand?
Given that if both doors are locked it equals 0 on the battlefield, you would think that, but no. When it's not on the battlefield, its mana value is equal to the total cost of both doors, and it has both names. I assume this is so that you can't pull Expertise tricks with it. If you want all the known stuff about it, take a look here.
Ok, thanks!
Point 2 seems all the odder, because the reminder text says "as a sorcery", but I guess it just means the stack needs to be empty and it is your turn so it's not an on-board trick rather than the oddness that is morph timings.
Probably there are ability triggers like "when a door unlocks". The reminder could be there to make clear that these effects also trigger when a room is cast and that it does not enter already unlocked.