38 cards where the text includes “can block only”

Air Bladder (Nemesis #28)
Ascending Aven (Onslaught #68)
Battlefield Percher (Nemesis #52)
Belbe's Percher (Nemesis #53)
Brazen Borrower // Petty Theft (Throne of Eldraine #39)
Chaosphere (Mirage #164)
Cloud Djinn (Vintage Masters #61)
Cloud Dragon (Masters Edition IV #41)
Cloud Elemental (Modern Masters 2015 #42)
Cloud Pirates (Portal #46)
Cloudseeder (Time Spiral Remastered #57)
Cloud Spirit (Masters Edition IV #42)
Cloud Sprite (Tenth Edition #75)
Dense Canopy (Saviors of Kamigawa #125)
Devoted Grafkeeper // Departed Soulkeeper (Innistrad: Midnight Hunt #218)
Devoted Grafkeeper // Departed Soulkeeper (Innistrad: Midnight Hunt #218)
Dreamcaller Siren (Ixalan #54)
Faerie Slumber Party (Wilds of Eldraine #311)
Gloomwidow (Shadows over Innistrad #206)
Hoverguard Observer (Darksteel #22)
Into the Fae Court (Wilds of Eldraine #57)
Long-Finned Skywhale (Kaladesh #54)
Novellamental (Unstable #41a)
Ominous Roost (Innistrad: Midnight Hunt #65)
Rishadan Airship (Jumpstart #170)
Rishadan Brigand (Mercadian Masques #92)
Scrapskin Drake (Duel Decks: Blessed vs. Cursed #47)
Shacklegeist (Crimson Vow Commander #112)
Skywinder Drake (Magic 2012 #75)
Soulcipher Board // Cipherbound Spirit (Innistrad: Crimson Vow #79)
Soulcipher Board // Cipherbound Spirit (Innistrad: Crimson Vow #79)
Stormbound Geist (Dark Ascension #51)
Stormcloud Djinn (Time Spiral Remastered #90)
Stratozeppelid (Guildpact #36)
Stratus Walk (Magic Origins #77)
Stronghold Zeppelin (Nemesis #47)
Tattered Haunter (Eldritch Moon #77)
Vaporkin (Conspiracy: Take the Crown #124)
Wanderlight Spirit (Innistrad: Crimson Vow #86)
Welkin Tern (Global Series Jiang Yanggu & Mu Yanling #5)

Though this query has ended, its relics still slumber in New Argive.