[15] Corey Plante, for Inverse, highlighted that the book adds a "larger unified theory of dragonkind" to the lore of the multiverse and delivers "the deepest dive into their origins that the game has ever seen".

[17] Plante wrote, "regardless of your party's level, there's plenty to look forward to in Fizban's hoard of knowledge to help inspire your next encounter, adventure, or whole campaign — even if it's an evil dragon killing its own echoes across the multiverse with the ultimate aim of dominating all of existence on the Material Plane".

Hall wrote that there are two primary uses of the book – the first is to help Dungeon Masters create a "personalized, high-level dragon villain (or ally) for those powerful characters to contend with" after they finish most campaign books (which end at around level 10) and that "canny DMs should be able to generate another five or more levels of gameplay after just a few hours' work".

Hall highlighted that the Draconomicon is "not a traditional bestiary" and instead acts as "a kind of miniature Player's Handbook built for DMs".

[18] Hoffer highlighted that "after the opening 30 pages, the rest of Fizban's Treasury of Dragons is meant primarily for the DM.

While Volo's Guide to Monsters and Mordenkainen's Tome of Foes touched on just about every corner of the D&D multiverse, Fizban's Treasury of Dragons felt much more like an 'old school' D&D supplement that expanded upon one aspect of the game.