Dungeons & Dragons: Adventures in the Forgotten Realms

Mordenkainen | Legendary Planeswalker | Mordenkainen | +2: Draw two cards, then put a card from your hand on the bottom of your library. −2: Create a blue Dog Illusion creature token with "This creature's power and toughness are each equal to twice the number of cards in your hand." −10: Exchange your hand and library, then shuffle. You get an emblem with "You have no maximum hand size." | Ryan Pancoast

Air-Cult Elemental | Creature | Elemental | Flying Whirlwind — When Air-Cult Elemental enters the battlefield, return up to one other target creature to its owner's hand. | Kari Christensen

True Polymorph | Instant | | Target artifact or creature becomes a copy of another target artifact or creature. | Steve Prescott

Sudden Insight | Instant | | Draw a card for each different mana value among nonland cards in your graveyard. | Dan Scott

Xanathar, Guild Kingpin | Legendary Creature | Beholder | At the beginning of your upkeep, choose target opponent. Until end of turn, that player can't cast spells, you may look at the top card of their library any time, you may play the top card of their library, and you may spend mana as though it were mana of any color to cast spells this way. | Kieran Yanner