You control up to five lands that can tap to produce ({3} magic symbol) ({U} magic symbol) ({U} magic symbol) plus enough mana to cast the other Aura spell after the lands are tapped twice.
Treachery by paying ({3} magic symbol) ({U} magic symbol) ({U} magic symbol) , targeting another creature.
Ivy triggers, copying
Treachery, with the copy targeting
Ivy.
Resolve the copy of
Treachery, attaching it to
Ivy.
When the
Treachery copy enters, it and
Cloudstone Curio triggers.
Resolve the
Treachery trigger, untapping up to five lands.
Resolve the
Cloudstone Curio trigger, returning nothing to your hand.
Resolve the original
Treachery, attaching it to the targeted creature and causing you to gain control of that creature.
When
Treachery enters, it and
Cloudstone Curio triggers.
Holding priority, activate up to five lands by tapping them, adding an amount of mana.
Resolve the
Treachery trigger, untapping up to five lands.
Resolve the
Cloudstone Curio trigger, returning the other Aura from the battlefield to your hand if it's on the battlefield. If it isn't on the battlefield, then return nothing to your hand.
Activate up to five lands by tapping them, adding an amount of mana.
Cast the other Aura by paying its mana cost, targeting another creature.
Ivy triggers, copying the Aura, with the copy targeting
Ivy.
Resolve the copy of the Aura, attaching it to
Ivy.
When the Aura copy enters,
Cloudstone Curio triggers. Choose to return nothing to your hand.
Resolve the original Aura, attaching it to the targeted creature.
When the Aura enters,
Cloudstone Curio triggers, returning the nontoken
Treachery from the battlefield to your hand.
Repeat.
Notes
The combo is written assuming the other Aura enchants a creature. If it doesn't, the combo will still function, but you will not get additional copies that attach to
Ivy. You can also elect to not have those copies attach to
Ivy, even if they do attach to creatures. To get infinite mana and untap of lands, you must use an Aura with mana value 4 or less, or have a land that adds multiple mana.
Results
Gain control of all creatures.
Infinite copies of a specific enchantment.
Infinite mana lands you control can produce.
Infinite storm count.
Infinite untap of lands you control.
Metadata
In 13 decks according to EDHREC.
Bracket Tag
This combo has been estimated to be Exhibition (Bracket 1+).