Chthonius is a playable dragon in Dragalia Lost.
One of the six legendary Greatwyrms who once accompanied the Founder King. Also known as the Netherwyrm, he wandered the abyss of death after his defeat, but now spreads his wings to stop the Other and fulfill his liege's dearest wish.
- Chthonius is the only member of the Greatwyrms who is not acquired via the main story (although he does appear in Chapter 10). Instead, he is acquired via summoning.