Originally posted by relentless1
there's no way you can prove that Night Kings spear would bounce off Smaug, sure he was able to shrug off mortal weapons but the black spear that did pierce him was about the same size as the javelins NK was using, not even counting the magic factor present here
You have it backwards, there's no way you can prove that the javelin can hurt him.
The dragons in GoT, even Drogon, are much smaller and weaker than Smaug.
Drogon is allegedly about 230 feet long.
https://www.businessinsider.com/game-of-thrones-dragons-size-747-plane-season-7-spoilers-2017-3
I say "allegedly" because I think that's a gross overestimation, but it doesn't matter, because Smaug is literally almost twice that length, at 130 meters/426 feet long:
https://www.fxguide.com/quicktakes/behind-the-scenes-of-weta-digitals-smaug/
That javelin impaled Viserion (who is even smaller and weaker than Drogon) sure, but it didn't go through, it stuck in. So it would be like stabbing Smaug with a boxcutter even if it did penetrate him.
Furthermore, dragons in GoT have glands on the sides of their mouths which produce their flames. If you pay attention, the Night King penetrated that gland, which is why there were explosions when he was stabbed. Smaug has no such weakness on the exterior of his body.
Smaug is considerably more powerful.