Flight and fire breath give the dragon overwhelming advantages the T-Rex simply can't counter.
The T-Rex is the most fearsome predator to ever walk the Earth, but it can't fly and it can't breathe fire. The European dragon can do both.
From the air, the dragon can rain fire on the T-Rex indefinitely, and the dinosaur has no way to respond. Its tiny arms can't swat at a flying target, and its powerful jaws are only useful if the dragon lands โ which it has no reason to do.
Even in a ground-based fight, the dragon's diamond-hard scales provide armor the T-Rex's 12,800 PSI bite would struggle to penetrate. The dragon's own claws and tail are devastating weapons at scale.
The T-Rex's only advantage is its bite force, and it can only use it if the dragon cooperates by coming within range. A dragon intelligent enough to hoard gold is intelligent enough to stay in the air.
Flight and fire breath make this a one-sided aerial bombardment. Diamond scales resist the T-Rex's bite. The dragon's intelligence means it would never willingly enter the T-Rex's bite range.
The T-Rex has the most powerful bite of any land animal ever. If the dragon lands for any reason โ overconfidence, weariness, close combat โ a single clean bite could be devastating. The T-Rex is also faster on the ground than most mythological dragon depictions suggest.
The dragon wins through air superiority. The T-Rex is an incredible predator but has no answer for flight and fire breath. This matchup highlights why dragons are mythology's apex predator โ they have no exploitable vulnerabilities.
Dragon (European) also fights
Tyrannosaurus Rex also fights