War of the Spark

God-Eternal Kefnet | Legendary Creature | Zombie God | Flying You may reveal the first card you draw each turn as you draw it. Whenever you reveal an instant or sorcery card this way, copy that card and you may cast the copy. That copy costs {2} less to cast. When God-Eternal Kefnet dies or is put into exile from the battlefield, you may put it into its owner's library third from the top. | Lius Lasahido

Rescuer Sphinx | Creature | Sphinx | Flying As Rescuer Sphinx enters the battlefield, you may return a nonland permanent you control to its owner's hand. If you do, Rescuer Sphinx enters the battlefield with a +1/+1 counter on it. | Jesper Ejsing

Spark Double | Creature | Illusion | You may have Spark Double enter the battlefield as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary. | Eric Deschamps

Thunder Drake | Creature | Elemental Drake | Flying Whenever you cast your second spell each turn, put a +1/+1 counter on Thunder Drake. | Yeong-Hao Han

Elite Guardmage | Creature | Human Wizard | Flying When Elite Guardmage enters the battlefield, you gain 3 life and draw a card. | PINDURSKI