Theros

Fabled Hero | Creature | Human Soldier | Double strike Heroic — Whenever you cast a spell that targets Fabled Hero, put a +1/+1 counter on Fabled Hero. | Aaron Miller

Meletis Charlatan | Creature | Human Wizard | {2}{U}, {T}: The controller of target instant or sorcery spell copies it. That player may choose new targets for the copy. | Jason A. Engle

Agent of the Fates | Creature | Human Assassin | Deathtouch Heroic — Whenever you cast a spell that targets Agent of the Fates, each opponent sacrifices a creature. | Matt Stewart

Nighthowler | Enchantment Creature | Horror | Bestow {2}{B}{B} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.) Nighthowler and enchanted creature each get +X/+X, where X is the number of creature cards in all graveyards. | Nils Hamm

Rageblood Shaman | Creature | Minotaur Shaman | Trample Other Minotaur creatures you control get +1/+1 and have trample. | Mike Bierek

Boon Satyr | Enchantment Creature | Satyr | Flash Bestow {3}{G}{G} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.) Enchanted creature gets +4/+2. | Wesley Burt

Reverent Hunter | Creature | Human Archer | When Reverent Hunter enters the battlefield, put a number of +1/+1 counters on it equal to your devotion to green. (Each {G} in the mana costs of permanents you control counts toward your devotion to green.) | Wesley Burt

Daxos of Meletis | Legendary Creature | Human Soldier | Daxos of Meletis can't be blocked by creatures with power 3 or greater. Whenever Daxos of Meletis deals combat damage to a player, exile the top card of that player's library. You gain life equal to that card's mana value. Until end of turn, you may cast that card and you may spend mana as though it were mana of any color to cast that spell. | Karla Ortiz

Anax and Cymede | Legendary Creature | Human Soldier | First strike, vigilance Heroic — Whenever you cast a spell that targets Anax and Cymede, creatures you control get +1/+1 and gain trample until end of turn. | Willian Murai