32 cards where the text matches the regex /counter target.*spell/ and the color identity ≤ BGRW and it’s legal in Commander

Artifact Blast (Masters Edition IV #108)
Avoid Fate (Time Spiral Timeshifted #73)
Burnout (Masters Edition II #121)
Dash Hopes (Planar Chaos #68)
Dawn Charm (Commander Legends #371)
Deathgrip (Masters Edition IV #75)
Equinox (Legends #13)
Frontline Medic (Commander Legends: Battle for Baldur's Gate #693)
Goblin Artisans (Chronicles #48)
Guttural Response (Duel Decks: Mind vs. Might #56)
Illumination (Mirage #21)
Jester's Scepter (Coldsnap #137)
Kozilek, the Great Distortion (Commander Masters #2)
Lapse of Certainty (Conflux #9)
Lifeforce (Masters Edition IV #160)
Mage's Attendant (Commander Legends: Battle for Baldur's Gate #698)
Mana Tithe (Time Spiral Remastered #26)
Molten Influence (Odyssey #207)
Not of This World (Commander Masters #807)
Null Brooch (Exodus #136)
Order of the Sacred Torch (Masters Edition II #25)
Pyroblast (Eternal Masters #142)
Rebuff the Wicked (Time Spiral Remastered #35)
Red Elemental Blast (Masters 25 #147)
Ring of Immortals (Legends #293)
Stromgald Cabal (Masters Edition II #113)
Thrull Wizard (Fallen Empires #46)
Tibalt's Trickery (Kaldheim #153)
Unyaro Griffin (Classic Sixth Edition #49)
Vigilant Martyr (Mirage #45)
Warping Wail (Commander Masters #812)
Withering Boon (Mirage #152)

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