Alright... weird enchantment question.

[Drealin]

piousflea brings up a good point about Nullify.  I would initially say that when your opponent reveals an enchantment you should destroy a same enchantment that you have.  However, it would be impossible to ensure that that happens.  Whether on purpose or accident, you can't know if you opponent should destroy their enchantment or not.
So for simplicity the rules should stand as they are for your own enchantments, and when multiple players are involved, you only take into account what is currently revealed.

[Gewar]

My vote goes for "when an enchantment is revealed and you know there is the duplicate, you must reveal and destroy the duplicate".

[DarthDadaD20]

I agree with that (what piousflea and Shad0w said) As I put in my previous post, but do you think that would lead to any confusion with your duplicating your own enchantments? (Like I said, so no one would think it was ok to have duplicate enchantments *on themselves* just because one was hidden) If none thinks that would cause any confusion,(Im looking at you Drealin/piousflea/Shad0w) then I am in all the way with it only taking into account what is currently revealed. (I just foresee confusion) Piousflea has made me think not. It should be clear that it is illegal, I was thinking more about teaching the game and should of made that clear.
edit: On the other hand with the talk about only destroying revealed enchantments....like piousflea suggested; then "he can legally leave it as a facedown enchantment and leave me guessing for the rest of the game." Is that kind of abuse? I like this ruling for simplicity but Im sort of playing devils advocate on this one. Thank you to everyone that is putting up with me here!  :dry:

[piousflea]

Illegal self duplication is easier to control than enemy duplication. If I dispel a bear strength on your Mage, and three rounds later you reveal another bear strength: either you have not cast any enchantments on yourself over the past three rounds, in which case I call you out for illegal casting, or you have cast enchantments on yourself in the meantime. In that case, you've spent a quick action and 2 mana so you've effectively paid the cost of re-enchanting.

That said, in an extremely high stakes tournament game, if one player has a large number of face downs, it could be reasonable to call a referee to make sure there are no duplicates.

[Drealin]

Illegal self duplication is easier to control than enemy duplication. If I dispel a bear strength on your Mage, and three rounds later you reveal another bear strength: either you have not cast any enchantments on yourself over the past three rounds, in which case I call you out for illegal casting, or you have cast enchantments on yourself in the meantime. In that case, you've spent a quick action and 2 mana so you've effectively paid the cost of re-enchanting.

That said, in an extremely high stakes tournament game, if one player has a large number of face downs, it could be reasonable to call a referee to make sure there are no duplicates.

I agree with everything you said.
For enemy duplication I think that the rule only comes into play for revealed enchantments, I don't think this will cause any real confusion, it's just a minor change from the self duplication rule.  Plus it is normally a very rare occurrence.
As far as having a face down enchantment making the other person guess for the rest of the game.  That can happen no matter what, and what Decoy's are for, if you decide to use a different enchantment than Decoy, I see no problem with that since you won't get your mana refunded ever.

[Snotwalker]

I think the issue of a duplicate Nulify is different from an enchantment that remains in play after being revealed.  

So if both my opponent and I have a Nulify on my creature, and I reveal nulify to cancel a spell, my opponent's nulify would still remain unrevealed on the creature seeing as how once mine is revealed, it is immediately discarded...  So as soon as my opponent realizes that there were two nulifys on the same creature (only one of them his), there now remains only one nulify enchantment on the creature, breaking no rules.

Why would he have to discard his now lone nulify?  He wouldn't.

And I have to admit, I never really considered casting a nulify on my opponent's creatures before... it could actually be an interesting tactic to try sometime.   B)

[Tacullu64]

There can't be 2 Nullify's on the same creature. The casting of the second by the opposing mage causes the first Nullify to be revealed (mandatory reveal icon on Nullify), at which point it's controller must decide to pay the reveal cost and cancel the second Nullify or not pay and let the second Nullify be attached to his creature. As a side note the controller of the first Nullify only knows his creature is being targeted with an enchantment at this point, not what that enchantment is.

[piousflea]

Oops, you're right, there can't be two nullifies.

However, the point remains that it is extremely difficult to referee whether or not a temporary enchantment "should have" destroyed a facedown duplicate. So the best idea is that the facedown duplicate should remain intact

[DarthDadaD20]

I think the issue of a duplicate Nulify is different from an enchantment that remains in play after being revealed.  

So if both my opponent and I have a Nulify on my creature, and I reveal nulify to cancel a spell, my opponent's nulify would still remain unrevealed on the creature seeing as how once mine is revealed, it is immediately discarded...  So as soon as my opponent realizes that there were two nulifys on the same creature (only one of them his), there now remains only one nulify enchantment on the creature, breaking no rules.

Why would he have to discard his now lone nulify?  He wouldn't.

And I have to admit, I never really considered casting a nulify on my opponent's creatures before... it could actually be an interesting tactic to try sometime.   B)

Well nullify is a mandatory reveal enchantment so that could never be the case. I cast nullify on my opponents warlock every chance I get! :evil:  (I hate the warlock so very, very much.)
edit I did not see the page 2! :blush:

[Tacullu64]

edit I did not see the page 2! :blush:

Yeah right. I know you're just trying to increase your post count cause it's killing you not knowing what your title will be at 400 posts. :lol:

[Snotwalker]

There can't be 2 Nullify's on the same creature. The casting of the second by the opposing mage causes the first Nullify to be revealed (mandatory reveal icon on Nullify), at which point it's controller must decide to pay the reveal cost and cancel the second Nullify or not pay and let the second Nullify be attached to his creature. As a side note the controller of the first Nullify only knows his creature is being targeted with an enchantment at this point, not what that enchantment is.

Since we're in "TheoryVille" here, actually there could potentially be 2 Nulifys on one creature.  How, you ask?  In Teamplay games.

If both I and an ally in a teamplay game cast nulify on an opposing mage, then yes, there could exist an example of 2 legaly cast nulifies on a single creature.

But I also admit that in a 2-player game, this could never happen.  My bad.  I was trying to think of both 1:1 and team games at the same time, and obviously had a Spell of Confusion cast upon me by a opposing mage.  (Hmmmm....  Spell of Confusion... interesting future enchantment release?...  When revealed, the intended spell's target is now cast upon a randomly determined creature instead, both ally and enemy considered alike?  Wow... I like that!)

[Aarrow]

There can't be 2 Nullify's on the same creature. The casting of the second by the opposing mage causes the first Nullify to be revealed (mandatory reveal icon on Nullify), at which point it's controller must decide to pay the reveal cost and cancel the second Nullify or not pay and let the second Nullify be attached to his creature. As a side note the controller of the first Nullify only knows his creature is being targeted with an enchantment at this point, not what that enchantment is.

Since we're in "TheoryVille" here, actually there could potentially be 2 Nulifys on one creature.  How, you ask?  In Teamplay games.

If both I and an ally in a teamplay game cast nulify on an opposing mage, then yes, there could exist an example of 2 legaly cast nulifies on a single creature.

But I also admit that in a 2-player game, this could never happen.  My bad.  I was trying to think of both 1:1 and team games at the same time, and obviously had a Spell of Confusion cast upon me by a opposing mage.  (Hmmmm....  Spell of Confusion... interesting future enchantment release?...  When revealed, the intended spell's target is now cast upon a randomly determined creature instead, both ally and enemy considered alike?  Wow... I like that!)

Even in team games the first Nullify HAS to trigger when the creature is targeted by ANYONE, even including the owner of Nullify.

[Snotwalker]

There can't be 2 Nullify's on the same creature. The casting of the second by the opposing mage causes the first Nullify to be revealed (mandatory reveal icon on Nullify), at which point it's controller must decide to pay the reveal cost and cancel the second Nullify or not pay and let the second Nullify be attached to his creature. As a side note the controller of the first Nullify only knows his creature is being targeted with an enchantment at this point, not what that enchantment is.

Since we're in "TheoryVille" here, actually there could potentially be 2 Nulifys on one creature.  How, you ask?  In Teamplay games.

If both I and an ally in a teamplay game cast nulify on an opposing mage, then yes, there could exist an example of 2 legaly cast nulifies on a single creature.

But I also admit that in a 2-player game, this could never happen.  My bad.  I was trying to think of both 1:1 and team games at the same time, and obviously had a Spell of Confusion cast upon me by a opposing mage.  (Hmmmm....  Spell of Confusion... interesting future enchantment release?...  When revealed, the intended spell's target is now cast upon a randomly determined creature instead, both ally and enemy considered alike?  Wow... I like that!)

Even in team games the first Nullify HAS to trigger when the creature is targeted by ANYONE, even including the owner of Nullify.

Nulify is only activated when an opposing mage casts an enchantment or incantation on the creature.

[Drealin]

There can't be 2 Nullify's on the same creature. The casting of the second by the opposing mage causes the first Nullify to be revealed (mandatory reveal icon on Nullify), at which point it's controller must decide to pay the reveal cost and cancel the second Nullify or not pay and let the second Nullify be attached to his creature. As a side note the controller of the first Nullify only knows his creature is being targeted with an enchantment at this point, not what that enchantment is.

Since we're in "TheoryVille" here, actually there could potentially be 2 Nulifys on one creature.  How, you ask?  In Teamplay games.

If both I and an ally in a teamplay game cast nulify on an opposing mage, then yes, there could exist an example of 2 legaly cast nulifies on a single creature.

But I also admit that in a 2-player game, this could never happen.  My bad.  I was trying to think of both 1:1 and team games at the same time, and obviously had a Spell of Confusion cast upon me by a opposing mage.  (Hmmmm....  Spell of Confusion... interesting future enchantment release?...  When revealed, the intended spell's target is now cast upon a randomly determined creature instead, both ally and enemy considered alike?  Wow... I like that!)

Even in team games the first Nullify HAS to trigger when the creature is targeted by ANYONE, even including the owner of Nullify.

Nulify is only activated when an opposing mage casts an enchantment or incantation on the creature.

Correct, Nullify specifically says when "targeted by an incantation or enchantment spell controlled by an opponent".
But the real question here is:

If an opponent reveals an enchantment on an object, and you have the same enchantment hidden on that object, are you required to let the opponent know that?
If yes, then what happens to each enchantment?

[Tacullu64]

There can't be 2 Nullify's on the same creature. The casting of the second by the opposing mage causes the first Nullify to be revealed (mandatory reveal icon on Nullify), at which point it's controller must decide to pay the reveal cost and cancel the second Nullify or not pay and let the second Nullify be attached to his creature. As a side note the controller of the first Nullify only knows his creature is being targeted with an enchantment at this point, not what that enchantment is.

Since we're in "TheoryVille" here, actually there could potentially be 2 Nulifys on one creature.  How, you ask?  In Teamplay games.

If both I and an ally in a teamplay game cast nulify on an opposing mage, then yes, there could exist an example of 2 legaly cast nulifies on a single creature.

But I also admit that in a 2-player game, this could never happen.  My bad.  I was trying to think of both 1:1 and team games at the same time, and obviously had a Spell of Confusion cast upon me by a opposing mage.  (Hmmmm....  Spell of Confusion... interesting future enchantment release?...  When revealed, the intended spell's target is now cast upon a randomly determined creature instead, both ally and enemy considered alike?  Wow... I like that!)

Even in team games the first Nullify HAS to trigger when the creature is targeted by ANYONE, even including the owner of Nullify.

Nulify is only activated when an opposing mage casts an enchantment or incantation on the creature.

Correct, Nullify specifically says when "targeted by an incantation or enchantment spell controlled by an opponent".
But the real question here is:

If an opponent reveals an enchantment on an object, and you have the same enchantment hidden on that object, are you required to let the opponent know that?
If yes, then what happens to each enchantment?

I believe Arcanus answered what happens to the first enchantment revealed. It stays in play and takes effect. The question is what happens to the face down enchantment? Does it stay in play or should it be shown and discarded.

It's a question that has to be answered, but I'm not sure how important it is since it shouldn't impact the game very much. I can see both sides and at the moment I'm kinda indifferent. Hopefully I'll get a feeling for which I prefer over the next couple of days.