A summoner, Yuna can conjure beings known as "aeons" to aid in combat
However, if we just look at what card is most impactful, what card adds the most to decks with it, I think youve got to give it to Faithless Looting
Esper Gift (1 player) : Thanks to Minister of Inquiriesanother Kaladesh Remastered reprintthere is now a critical mass of cheap mill effects to put the trio of Scholar of the Lost Trove, Unburial Rites, and God-Pharaoh's Gift into the graveyard
#1: Teferi, Temporal Pilgrim Teferi, Temporal Pilgrim is the monarch of blue cards from The Brothers War
Theres also the survivor creatures from Duskmourn : theyre meant to trigger when they survive combat, but its way easier to just saddle or station with them before our second main phase
Ghost-Lit Stalker isnt very good after sideboarding because of how fast the matchup is, but Myojin is kept in as it sometimes is a good target for Time of Need or Gifts