29 cards where the mana value = 4 and the colors is R and the card types include “dragon”

Arcbound Whelp (Modern Horizons 2 #113)
Archwing Dragon (Avacyn Restored #126)
Atsushi, the Blazing Sky (Kamigawa: Neon Dynasty #134)
Avaricious Dragon (Magic Origins #131)
A-Young Red Dragon // A-Bathe in Gold (Alchemy Horizons: Baldur's Gate #A-197)
Decadent Dragon // Expensive Taste (Wilds of Eldraine #223)
Dragonborn Immolator (Alchemy Horizons: Baldur's Gate #51)
Dragon Whelp (Dominaria Remastered #116)
Fledgling Dragon (Judgment #90)
Furnace Whelp (Jumpstart #323)
Jaded Sell-Sword (Adventures in the Forgotten Realms #152)
Leyline Tyrant (Zendikar Rising #147)
Lightning Dragon (Vintage Masters #177)
Manaform Hellkite (Innistrad: Crimson Vow #170)
Moonveil Regent (Innistrad: Midnight Hunt #149)
Nalathni Dragon (Magic Online Promos #35956)
Opportunistic Dragon (Forgotten Realms Commander #134)
Rakdos Pit Dragon (Ravnica Remastered #120)
Rathi Dragon (Tempest Remastered #150)
Scion of Shiv (Jumpstart: Historic Horizons #24)
Skyship Stalker (Forgotten Realms Commander #141)
Stingerback Terror (Outlaws of Thunder Junction #147)
Stirring Bard (Commander Legends: Battle for Baldur's Gate #195)
Territorial Hellkite (Commander Legends: Battle for Baldur's Gate #809)
Thunderbreak Regent (Forgotten Realms Commander #147)
Town-Razer Tyrant (Alchemy: Innistrad #45)
Vengeful Ancestor (Murders at Karlov Manor Commander #163)
Verix Bladewing (Dominaria #149)
Young Red Dragon // Bathe in Gold (Commander Legends: Battle for Baldur's Gate #210)

It is the moment of discovery, the triumph of the mind, and the end of these results.