Ivy, Gleeful Spellthief + Cloudstone Curio + Treachery

Ivy, Gleeful Spellthief

Cloudstone Curio

Treachery

How it works

1. Cast Treachery by paying 3, targeting another creature.
2. Ivy triggers, copying Treachery, with the copy targeting Ivy.
3. Resolve the copy of Treachery, attaching it to Ivy.
4. When the Treachery copy enters, it and Cloudstone Curio triggers.
5. Resolve the Treachery trigger, untapping up to five lands.
6. Resolve the Cloudstone Curio trigger, returning nothing to your hand.
7. Resolve the original Treachery, attaching it to the targeted creature and causing you to gain control of that creature.
8. When Treachery enters, it and Cloudstone Curio triggers.
9. Holding priority, activate up to five lands by tapping them, adding an amount of mana.
10. Resolve the Treachery trigger, untapping up to five lands.
11. 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.
12. Activate up to five lands by tapping them, adding an amount of mana.
13. Cast the other Aura by paying its mana cost, targeting another creature.
14. Ivy triggers, copying the Aura, with the copy targeting Ivy.
15. Resolve the copy of the Aura, attaching it to Ivy.
16. When the Aura copy enters, Cloudstone Curio triggers. Choose to return nothing to your hand.
17. Resolve the original Aura, attaching it to the targeted creature.
18. When the Aura enters, Cloudstone Curio triggers, returning the nontoken Treachery from the battlefield to your hand.
19. Repeat.