A bit of Fridge Brilliance at the end of the film, Liz melts down the Crown so nobody else can activate the titular Golden Army, the brilliance kicks in when you think about one fact: Why has nobody tried this before? one answer is that the elves (rightly) never trusted the humans to keep their word, and as shown by the prince, the elves are superior in skill to humans in fighting, so taking back the piece they gave would be no problem. Another answer is the fact that the elf king always knew the fae world would die out and therefore was waiting for it to be maybe a few or at least just himself left before melting it down, as with the fae world still alive there would always have been a chance for the Crown to simply be reforged. a small bit of horror then kicks in at the fact that, as shown by the troll market, there still are plenty of Fae creatures left, including the smith who made the army himself, what if he decided to stop regretting and start getting angry?
Fridge / Hellboy II: The Golden Army