36 cards where the card is tagged “opening-card”

Backup Plan (Conspiracy #2)
Buried Ogre (Mystery Booster Playtest Cards 2021 #36)
Chancellor of the Annex (New Phyrexia #6)
Chancellor of the Dross (New Phyrexia #54)
Chancellor of the Forge (New Phyrexia #81)
Chancellor of the Spires (New Phyrexia #31)
Chancellor of the Tangle (New Phyrexia #106)
Cryptic Spires (Double Masters 2022 #332)
Elvish Champion Avatar (Magic Online Avatars #37)
Emissary's Ploy (Conspiracy: Take the Crown #4)
Gemstone Caverns (Time Spiral Remastered #280)
Impatient Iguana (Mystery Booster Playtest Cards 2021 #55)
Ink-Eyes, Servant of Oni Avatar (Magic Online Avatars #48)
Leyline of Abundance (Core Set 2020 #179)
Leyline of Anticipation (Commander Legends: Battle for Baldur's Gate #726)
Leyline of Combustion (Core Set 2020 #148)
Leyline of Lifeforce (Guildpact #90)
Leyline of Lightning (Guildpact #68)
Leyline of Punishment (Magic 2011 #148)
Leyline of Sanctity (Core Set 2020 #26)
Leyline of Singularity (Guildpact #29)
Leyline of the Guildpact (Murders at Karlov Manor #217)
Leyline of the Meek (Guildpact #10)
Leyline of the Void (Core Set 2020 #107)
Leyline of Vitality (Magic 2011 #183)
Maralen of the Mornsong Avatar (Magic Online Avatars #78)
Once Upon a Time (Throne of Eldraine #169)
Photo Op (Unfinity #83)
Providence (Eldritch Moon #37)
Rift (Mystery Booster Playtest Cards 2021 #119)
Serum Powder (Iconic Masters #228)
Seshiro the Anointed Avatar (Magic Online Avatars #46)
Sphinx of Foresight (Ravnica Allegiance #55)
The Slayer (Theros Hero's Path #3)
The Vanquisher (Born of the Gods Hero's Path #6)
Time Sidewalk (Mystery Booster Playtest Cards 2021 #31)

The message was clear to Sorin—time to search for something else.