March of the Machine

Invasion of Arcavios // Invocation of the Founders | Battle // Enchantment | Siege // | (As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.) When Invasion of Arcavios enters, search your library, graveyard, and/or outside the game for an instant or sorcery card you own, reveal it, and put it into your hand. If you search your library this way, shuffle. // Whenever you cast an instant or sorcery spell from your hand, you may copy that spell. You may choose new targets for the copy. | Dmitry Burmak

Hidetsugu and Kairi | Legendary Creature | Ogre Demon Dragon | Flying When Hidetsugu and Kairi enters the battlefield, draw three cards, then put two cards from your hand on top of your library in any order. When Hidetsugu and Kairi dies, exile the top card of your library. Target opponent loses life equal to its mana value. If it's an instant or sorcery card, you may cast it without paying its mana cost. | Chris Rahn

Invasion of Alara | Battle | Siege | When Invasion of Alara enters the battlefield, exile cards from the top of your library until you exile two nonland cards with mana value 4 or less. You may cast one of those two cards without paying its mana cost. Put one of them into your hand. Then put the other cards exiled this way on the bottom of your library in a random order. | Mathias Kollros

Omnath, Locus of All | Legendary Creature | Phyrexian Elemental | If you would lose unspent mana, that mana becomes black instead. At the beginning of your precombat main phase, look at the top card of your library. You may reveal that card if it has three or more colored mana symbols in its mana cost. If you do, add three mana in any combination of its colors and put it into your hand. If you don't reveal it, put it into your hand. | Bryan Sola