40 cards where the number of colors is 3 and (the card types include “dragon” or the full Oracle text includes “dragon”)

Miirym, Sentinel Wyrm (Commander Legends: Battle for Baldur's Gate #284)
Ziatora, the Incinerator (Streets of New Capenna #231)
Korvold, Fae-Cursed King (Throne of Eldraine #329)
Nicol Bolas, Dragon-God (Ravnica Remastered #205)
Kaalia of the Vast (Double Masters 2022 #235)
Nicol Bolas, the Ravager // Nicol Bolas, the Arisen (Core Set 2019 #218)
Nicol Bolas, the Ravager // Nicol Bolas, the Arisen (Core Set 2019 #218)
Rith, Liberated Primeval (Dominaria United #214)
Sarkhan Unbroken (Dragons of Tarkir #230)
Arcades, the Strategist (Core Set 2019 #212)
Teneb, the Harvester (Double Masters 2022 #282)
Karrthus, Tyrant of Jund (Double Masters #205)
Piru, the Volatile (Modern Horizons 2 #207)
Prossh, Skyraider of Kher (Masters 25 #214)
Vaevictis Asmadi, the Dire (Core Set 2019 #225)
Kaalia, Zenith Seeker (Core Set 2020 #210)
Intet, the Dreamer (Double Masters 2022 #229)
Wasitora, Nekoru Queen (Double Masters 2022 #293)
Amareth, the Lustrous (Commander Legends #266)
Zurgo and Ojutai (March of the Machine #258)
Goro-Goro and Satoru (March of the Machine Commander #445)
Nicol Bolas (Masters 25 #209)
Crosis, the Purger (Commander 2017 #168)
Darigaaz Reincarnated (Dominaria #193)
Broodmate Dragon (Commander 2017 #165)
Rith, the Awakener (Dominaria Remastered #198)
Hellkite Overlord (Double Masters 2022 #225)
Chromium, the Mutable (Core Set 2019 #214)
Palladia-Mors, the Ruiner (Core Set 2019 #219)
Numot, the Devastator (Commander 2011 #215)
Korvold, Gleeful Glutton (Wilds of Eldraine Commander #26)
Oros, the Avenger (Commander Anthology #188)
Vorosh, the Hunter (Commander Anthology Volume II #3)
Dromar, the Banisher (Invasion #244)
Treva, the Renewer (Duel Decks: Phyrexia vs. the Coalition #49)
Darigaaz, the Igniter (Duel Decks: Phyrexia vs. the Coalition #47)
Vaevictis Asmadi (Masters Edition III #185)
Arcades Sabboth (Dominaria Remastered #187)
Chromium (Masters Edition III #147)
Palladia-Mors (Masters Edition III #164)
Darigaaz, Shivan Champion (Alchemy: Dominaria #22)

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