[Sounds good to him!!]

I don't mind. The cave I'm thinking of is a passage through the mountains called the Weasand of Cados. It's home to an aer krene - essentially a place with a high density of aer.

[Don't worry, he's getting to the explanation of it, since that's apparently not a thing other jrpg worlds have!!]

Aer - not the same as the air we breathe, mind you! - is everywhere in my world; it powers our blastia and has a large impact on our world, and normally it isn't visible. Too much aer can cause things to grow out of control - there was a forest dealing with that not all that far from Dahngrest, if I'm not mistaken.

[...it was also kinda sorta close to his house, but like hell if he was gonna deal with that.]

Without the aer krene, it likely would have been a normal cave. But because it was so thick and nearly out of control, it gave the place a very surreal feeling. The monsters there were also quite unique - I imagine that's why they turned out differently than their counterparts elsewhere.

[sometimes you just gotta have weird monster designs, you know how it is.]