Gate of the Infinite Spiral

Indestructible

At the beginning of each opponent's upkeep, that player exiles the top four cards of their library.

You may play cards exiled with Gate of the Infinite Spiral, and you may spend mana as though it were mana of any color to cast them.

When Gate of the Infinite Spiral leaves the battlefield, return all remaining cards exiled with it to their owners' graveyards.