26 cards where the mana value >= 8 and it’s not legal in Commander

A-Earthquake Dragon (Alchemy Horizons: Baldur's Gate #A-209)
Angelic Rocket (Unstable #139)
B.F.M. (Big Furry Monster) (Unglued #28)
B.F.M. (Big Furry Monster) (Unglued #29)
Biorhythm (Ninth Edition #231)
Coalition Victory (Time Spiral Timeshifted #91)
Colossal Chorus (Alchemy: Ixalan #18)
Emrakul, the Aeons Torn (Double Masters 2022 #1)
Everythingamajig (Unstable #147f)
Gleemax (Unhinged #121)
Granny's Payback (Unhinged #99)
Greater Morphling (Unhinged #34)
Griselbrand (Modern Masters 2017 #72)
Incoming! (Unglued #64)
Infernal Spawn of Evil (Unsanctioned #38)
Infernal Spawn of Infernal Spawn of Evil (Unsanctioned #39)
Infernius Spawnington III, Esq. (Unsanctioned #40)
Iona, Shield of Emeria (Modern Masters 2015 #20)
Mox Lotus (Unhinged #124)
Omniclown Colossus // Pie-roclasm (Unfinity #116)
Summon the Pack (Unstable #74)
Sundering Titan (Double Masters #292)
Sway of the Stars (Betrayers of Kamigawa #54)
Uktabi Kong (Unhinged #115)
Verdant Rejuvenation (Alchemy Horizons: Baldur's Gate #69)
Who // What // When // Where // Why (Unsanctioned #75)

In the blink of an eye, they strode from deep snow to the end of this search.