55 cards where the card types include “demon” and the card types include “legendary” and it’s legal in Commander

Be'lakor, the Dark Master (Warhammer 40,000 Commander #6)
Demonlord Belzenlok (Commander Masters #151)
Elbrus, the Binding Blade // Withengar Unbound (Dark Ascension #147)
Elbrus, the Binding Blade // Withengar Unbound (Dark Ascension #147)
Falco Spara, Pactweaver (Streets of New Capenna #186)
Gyruda, Doom of Depths (Ikoria: Lair of Behemoths #221)
Hidetsugu and Kairi (March of the Machine #228)
Hidetsugu, Devouring Chaos (Kamigawa: Neon Dynasty #99)
Imskir Iron-Eater (Modern Horizons 3 #189)
Jerren, Corrupted Bishop // Ormendahl, the Corrupter (Innistrad: Midnight Hunt #109)
Jerren, Corrupted Bishop // Ormendahl, the Corrupter (Innistrad: Midnight Hunt #109)
Jetmir, Nexus of Revels (Streets of New Capenna #193)
Kagemaro, First to Suffer (Saviors of Kamigawa #73)
Kardur, Doomscourge (Duskmourn: House of Horror Commander #223)
Kothophed, Soul Hoarder (Dominaria United Commander #114)
Krav, the Unredeemed (Battlebond #4)
Kuro, Pitlord (Duel Decks Anthology: Divine vs. Demonic #44)
Kyoki, Sanity's Eclipse (Betrayers of Kamigawa #72)
Lady Orca (Masters Edition III #159)
Lord Xander, the Collector (Streets of New Capenna #197)
Magnus the Red (Warhammer 40,000 Commander #131)
Malfegor (Iconic Masters #205)
Mortarion, Daemon Primarch (Warhammer 40,000 Commander #41)
Nefarox, Overlord of Grixis (Magic 2013 #103)
Ob Nixilis, Captive Kingpin (March of the Machine: The Aftermath #41)
Ob Nixilis, the Fallen (Iconic Masters #101)
Ob Nixilis, Unshackled (Double Masters 2022 #84)
Orca, Siege Demon (Dominaria United Commander #37)
Orcus, Prince of Undeath (Adventures in the Forgotten Realms #229)
Raffine, Scheming Seer (Streets of New Capenna #213)
Rakdos, Lord of Riots (Duskmourn: House of Horror Commander #230)
Rakdos, Patron of Chaos (Murders at Karlov Manor #224)
Rakdos the Defiler (Dissension #129)
Rakdos, the Muscle (Outlaws of Thunder Junction #226)
Rakdos, the Showstopper (Ravnica: Clue Edition #205)
Razaketh, the Foulblooded (Commander Masters #181)
Seizan, Perverter of Truth (Champions of Kamigawa #143)
Shelob, Child of Ungoliant (The Lord of the Rings: Tales of Middle-earth #230)
Shelob, Dread Weaver (Tales of Middle-earth Commander #29)
Shilgengar, Sire of Famine (Modern Horizons 3 #109)
Shimatsu the Bloodcloaked (Champions of Kamigawa #186)
Sol'kanar the Swamp King (Dominaria Remastered #200)
Sol'Kanar the Tainted (Dominaria United #219)
Spirit of the Night (Mirage #146)
Taborax, Hope's Demise (Commander Masters #189)
The Balrog, Durin's Bane (The Lord of the Rings: Tales of Middle-earth #195)
The Balrog, Flame of Udûn (The Lord of the Rings: Tales of Middle-earth #297)
The Balrog of Moria (Tales of Middle-earth Commander #46)
The Beast, Deathless Prince (Doctor Who #114)
Valgavoth, Harrower of Souls (Duskmourn: House of Horror Commander #6)
Valgavoth, Terror Eater (Duskmourn: House of Horror #120)
Varragoth, Bloodsky Sire (Kaldheim #115)
Vilis, Broker of Blood (Core Set 2020 #122)
Vito, Fanatic of Aclazotz (The Lost Caverns of Ixalan #243)
Westvale Abbey // Ormendahl, Profane Prince (Shadows over Innistrad #281)
Westvale Abbey // Ormendahl, Profane Prince (Shadows over Innistrad #281)
Yukora, the Prisoner (Betrayers of Kamigawa #90)
Ziatora, the Incinerator (Streets of New Capenna #231)

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