45 cards where the card types include “horse” and it’s legal in Commander

Akroan Horse (Commander 2016 #241)
Armored Warhorse (Magic 2012 #7)
Bill the Pony (The Lord of the Rings: Tales of Middle-earth #3)
Black Carriage (Homelands #42)
Breaching Hippocamp (Theros #43)
Bronze Horse (Masters Edition IV #186)
Calamity, Galloping Inferno (Outlaws of Thunder Junction #116)
Carnival Hellsteed (Return to Ravnica #147)
Caustic Bronco (Outlaws of Thunder Junction #82)
Chrome Steed (Scars of Mirrodin #142)
Clockwork Steed (Masters Edition II #205)
Cobbled Lancer (Innistrad: Crimson Vow #52)
Cosmos Charger (Kaldheim #51)
Crested Sunmare (Hour of Devastation #6)
Diamond Mare (Core Set 2019 #231)
Dusk Charger (Rivals of Ixalan #69)
Dwarven Pony (Homelands #70)
Fleshmad Steed (Theros #88)
Ghoulsteed (Ultimate Masters #97)
Hipparion (Fifth Edition #34)
Keleth, Sunmane Familiar (Commander Masters #33)
Lightning Mare (Core Set 2019 #151)
Motivated Pony (Tales of Middle-earth Commander #42)
Nightmare (Welcome Deck 2017 #17)
Phantasmal Mount (Masters Edition II #59)
Phantom Steed (Forgotten Realms Commander #18)
Phyrexian Warhorse (Dominaria United #101)
Plague Mare (Core Set 2019 #114)
Sacred Prey (Mercadian Masques #268)
Shadowfax, Lord of Horses (The Lord of the Rings: Tales of Middle-earth #227)
Shield Mare (Core Set 2019 #37)
Stallion of Ashmouth (Shadows over Innistrad #136)
Surge Mare (Core Set 2019 #77)
Tarpan (Fifth Edition #330)
Temur Charger (Khans of Tarkir #153)
Thundering Mightmare (Crimson Vow Commander #37)
Thundermare (Ninth Edition #224)
Timbermare (Planar Chaos #140)
Trenching Steed (Prophecy #26)
Underworld Charger (Theros Beyond Death #120)
Vine Mare (Core Set 2019 #207)
Wandermare (Throne of Eldraine #204)
Wavebreak Hippocamp (Theros Beyond Death #80)
Workhorse (Exodus #142)
Zodiac Horse (Portal Three Kingdoms #159)

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