The Lost Caverns of Ixalan

Ojer Pakpatiq, Deepest Epoch | Legendary Creature | God | Flying Whenever you cast an instant spell from your hand, it gains rebound. (Exile it as it resolves. At the beginning of your next upkeep, you may cast it from exile without paying its mana cost.) When Ojer Pakpatiq dies, return it to the battlefield tapped and transformed under its owner's control with three time counters on it. | Chris Rahn

The Ancient One | Legendary Creature | Spirit God | Descend 8 — The Ancient One can't attack or block unless there are eight or more permanent cards in your graveyard. {2}{U}{B}: Draw a card, then discard a card. When you discard a card this way, target player mills cards equal to its mana value. | Victor Adame Minguez

Saheeli, the Sun's Brilliance | Legendary Creature | Human Artificer | {U}{R}, {T}: Create a token that's a copy of another target creature or artifact you control, except it's an artifact in addition to its other types. It gains haste. Sacrifice it at the beginning of the next end step. | Cynthia Sheppard