Can the dragon die in chapter 4 dungeon level 5?

Each weapon I have tried so far (each magical element) only deals -1 damage regardless how strong they are. Perhaps getting the "Special Dragon Vest" when you complete dungeons 1-3 without injuries will help..?? I have one more level to complete before I can try that. Considering one of the achievements mentions something about passing through the portal I guess there should be a way considering someone earlier mentioned needing a dragon skull to get through ...??

No you can't. Every weapon deals a -1 damage only. Eventually you'll be able to kill it in level 39.

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