When it's defeated, exile it, then cast it transformed.) When this Siege enters, return up to three target permanent cards from your graveyard to your hand
The two best decks in the format right now, Deaths Shadow and Hammer Time, both play Thoughtseize, with it also being one of the most important cards in the formers deck
You sacrifice flying creatures but you get to do more things with your own creatures on your turn, and bouncing cards of theirs with Man-o'-War and Tradewind Rider could deal with things you don't want to give to other players but don't want the original player to have, either
Transforming Double-Faced Cards: Double-faced cards return, allowing players to cast the front face for its mana cost and transform it to the back face upon meeting specific conditions
The Sundials ability ends the turn
I ended up with seven lands that produce my two colors of mana, seven Swamps and seven Plains, and three lands that offer some utility