The dragon that guards the Lestrange vault at Gringotts in 'Harry Potter' is a Ukrainian Ironbelly. I love how blunt and epic that feels — the books describe it as massive, with hide like iron and a temperament to match, and later bits of canon (and J.K. Rowling's extra notes) make the Ukrainian Ironbelly the clear match for that role. Pottermore-era lore and companion material emphasize that this breed is one of the largest and most ferocious, bred for strength and used in situations where sheer power and intimidation are needed.
Watching Harry, Hermione, and Ron ride that dragon out of Gringotts in 'Deathly Hallows' is one of the most cinematic moments in the series for me. The Ironbelly’s brute force and almost armor-like scales are what make it a believable bank guardian, and comparing it to other breeds like the Hungarian Horntail or Norwegian Ridgeback highlights how specialized it is: not just fire and flight, but built to shrug off attacks and scare trespassers away. It always gives me a thrill thinking about dragons being treated as both terrifying beasts and, sometimes, unexpected allies.