Lyric discussion by LuluGo 

In my opinion, the song is about inner struggles such as fighting depression, anxiety, dark thoughts, suicide thoughts, intrusive thoughts or any shitty thing that brings us down...

Dragons are known to keep treasures inside mountains, The Moutain is ourselves, containing our treasure (Heart, Soul, Spirit) and is being held prisoner by dark things, a Dragon in that case..

Sometimes the Dragon doesn't dwell, he is silent, almost inexistant but once you start falling apart and dig within yourself, he comes back guarding your treasure, though you don't want him to...

So you have to fight it, it's the metaphor of the song, you're like a warrior fighting a Dragon in the cave of a mountain but sometimes the fight is hard, hopeless and the monsters devours you...

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