If you're here, it's because you're interested in Aura Swap. Let's get into it.

What is Aura Swap?

Aura Swap is a keyword ability (a set of text which represents an ability). It represents an activated ability allowing you to switch the Aura with Aura Swap with an Aura in your Hand. It debuted in Future Sight.

Sounds cool. Now what?

As of this writing, Aura Swap has been printed on ... exactly one card.

Arcanum Wings

Because of this, it is inherently a Blue ability.

Okay, how does it work?

With the Aura with Aura Swap on the Battlefield, you pay the cost associated and the ability goes on the stack. As it resolves, you may choose an Aura currently in your Hand. The game will check to make sure the Aura you've chosen can enchant the permanent with the Aura Swap Aura (in the case of Arcanum Wings, the Aura you choose must be able to Enchant a Creature).

Assuming the Aura with Aura Swap is still on the 'field, you put it in your Hand and you put the Aura you chose from your Hand and attach it to the permanent to be enchanted.

A couple of notes about this.

• The exchange, should it happen, happens simultaneously. At no point will the permanent be Enchanted by both Auras, nor will it not be Enchanted.
• If either half of the exchange can't happen, nothing happens. In other words, if the Aura with Aura Swap is gone, the Aura you choose can't Enchant the permanent in question, or if you simply don't have an Aura to choose, the ability will fizzle and you'll just be down three mana.
• If a non-Aura somehow gets Aura Swap, nothing happens (a non-Aura can't Enchant a permanent).

Anything else?

That's really it. It has a Storm Scale of 6; Mark Rosewater has said it's likely to return, probably in an Aura-focused set, but that it's dangerous because it circumvents mana costs (somehow getting to drop Eldrazi Conscription for three mana does seem dangerous).

Note like other Activated Abilities, Aura Swap can happen at Instant speed, which can make the ability quite powerful. In the right shell, it could provide you with incredible value.

Thanks for reading.