MAGIC: THE GATHERING
(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.)
Target player takes an extra turn after this one. Return up to one target nonland permanent to its owner's hand. Exile Karn's Temporal Sundering.
If you have a legendary creature or planeswalker in play, Karn's Temporal Sundering provides a ton of value. Get a crucial blocker off the battlefield and give yourself two turns to swing in!