Situation goes like this:
I have a permanent, lets say Arbor Elf.
I give my Arbor Elf away to another player using something like Zedruu the Greathearted, or Harmless Offering
I play Cast Out on that Arbor Elf that I own but which I have transferred control to another player.
Then I play Brand, which resolves.
Then my Cast Out is removed and is no longer holding the Arbor Elf in exile.
Under which player's control does Arbor Elf enter the battlefield? Mine or my opponent's?
It will enter under your control because that is how One-Shot effects work. Brand is basically irrelevant in this situation. It does not affect Arbor Elf because it is not on the battlefield (and, thus, not a permanent) but once Cast Out leaves, you get your card back anyway. This would happen whether you cast Brand or not.
Is there specific rules for these "One Shot" cards? I can understand if the Cast Out in the above situation was Detention Sphere, as it explicitly says "under owner's control". Cast Out does not have the clause about owner's control.
Detention Sphere is not a One-Shot effect. The "new" effects that are all part of the same trigger fall into this category. O-Ring and D-Sphere have 2 different triggers.
Here is the rule you requested for the interaction with Cast Out (the relevant rule is bolded but I provided the whole section to give some context):
610. One-Shot Effects
610.1. A one-shot effect does something just once and doesn't have a duration. Examples include dealing damage, destroying a permanent, creating a token, and moving an object from one zone to another.
610.2. Some one-shot effects create a delayed triggered ability, which instructs a player to do something later in the game (usually at a specific time) rather than as the spell or ability that's creating the one-shot effect resolves. See rule 603.7.
610.3. Some one-shot effects cause an object to change zones "until" a specified event occurs. A second one-shot effect is created immediately after the specified event. This second one-shot effect returns the object to its previous zone.
610.3a. If the specified event has already occurred when the initial one-shot effect would cause the object to change zones, the object doesn't move.
610.3b. An object returned to the battlefield this way returns under its owner's control unless otherwise specified.
610.3c. If multiple one-shot effects are created this way immediately after one or more simultaneous events, those one-shot effects are also simultaneous.
Example: Two Banisher Priests have each exiled a card. All creatures are destroyed at the same time by Day of Judgment. The two exiled cards are returned to the battlefield at the same time.
610. One-Shot Effects
[...]
610.3. Some one-shot effects cause an object to change zones “until” a specified event occurs. A second one-shot effect is created immediately after the specified event. This second one-shot effect returns the object to its previous zone.
[...] 610.3b An object returned to the battlefield this way returns under its owner’s control unless otherwise specified.
[...]
I have a permanent, lets say Arbor Elf.
I give my Arbor Elf away to another player using something like Zedruu the Greathearted, or Harmless Offering
I play Cast Out on that Arbor Elf that I own but which I have transferred control to another player.
Then I play Brand, which resolves.
Then my Cast Out is removed and is no longer holding the Arbor Elf in exile.
Under which player's control does Arbor Elf enter the battlefield? Mine or my opponent's?
Here is the rule you requested for the interaction with Cast Out (the relevant rule is bolded but I provided the whole section to give some context):
610.1. A one-shot effect does something just once and doesn't have a duration. Examples include dealing damage, destroying a permanent, creating a token, and moving an object from one zone to another.
610.2. Some one-shot effects create a delayed triggered ability, which instructs a player to do something later in the game (usually at a specific time) rather than as the spell or ability that's creating the one-shot effect resolves. See rule 603.7.
610.3. Some one-shot effects cause an object to change zones "until" a specified event occurs. A second one-shot effect is created immediately after the specified event. This second one-shot effect returns the object to its previous zone.
610.3a. If the specified event has already occurred when the initial one-shot effect would cause the object to change zones, the object doesn't move.
610.3b. An object returned to the battlefield this way returns under its owner's control unless otherwise specified.
610.3c. If multiple one-shot effects are created this way immediately after one or more simultaneous events, those one-shot effects are also simultaneous.
Example: Two Banisher Priests have each exiled a card. All creatures are destroyed at the same time by Day of Judgment. The two exiled cards are returned to the battlefield at the same time.
Former Rules Advisor
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