Foundations

Herald of Eternal Dawn | Creature | Angel | Flash (You may cast this spell any time you could cast an instant.) Flying You can't lose the game and your opponents can't win the game. | Martina Fačková

Sphinx of Forgotten Lore | Creature | Sphinx | Flash (You may cast this spell any time you could cast an instant.) Flying Whenever this creature attacks, target instant or sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to that card's mana cost. (You may cast that card from your graveyard for its flashback cost. Then exile it.) | Dmitry Burmak

Bloodthirsty Conqueror | Creature | Vampire Knight | Flying, deathtouch Whenever an opponent loses life, you gain that much life. (Damage causes loss of life.) | Dmitry Burmak

Twinflame Tyrant | Creature | Dragon | Flying If a source you control would deal damage to an opponent or a permanent an opponent controls, it deals double that damage instead. | Xabi Gaztelua

Quilled Greatwurm | Creature | Wurm | Trample Whenever a creature you control deals combat damage during your turn, put that many +1/+1 counters on it. (It must survive to get the counters.) You may cast this card from your graveyard by removing six counters from among creatures you control in addition to paying its other costs. | Michal Ivan

Niv-Mizzet, Visionary | Legendary Creature | Dragon Wizard | Flying You have no maximum hand size. Whenever a source you control deals noncombat damage to an opponent, you draw that many cards. | Dan Murayama Scott

Zimone, Paradox Sculptor | Legendary Creature | Human Wizard | At the beginning of combat on your turn, put a +1/+1 counter on each of up to two target creatures you control. {G}{U}, {T}: Double the number of each kind of counter on up to two target creatures and/or artifacts you control. | Nathaniel Himawan

Muldrotha, the Gravetide | Legendary Creature | Elemental Avatar | During each of your turns, you may play a land and cast a permanent spell of each permanent type from your graveyard. (If a card has multiple permanent types, choose one as you play it.) | Jason Rainville

Progenitus | Legendary Creature | Hydra Avatar | Protection from everything If Progenitus would be put into a graveyard from anywhere, reveal Progenitus and shuffle it into its owner's library instead. | Jaime Jones

Sire of Seven Deaths | Creature | Eldrazi | First strike, vigilance Menace, trample Reach, lifelink Ward—Pay 7 life. | Lius Lasahido