Originally posted by PGxRiver:

I think it would be great if I could build a cave

Not EXACTLY the same as a "cave", but you can dig out underneath Elder altar which makes a very safe underground base... the top is completely indestructible, and I have never had any mob actually get inside.

I added wood walls in mine but you could leave it just as dirt walls to give it a cave "atmosphere"

https://steamcommunity.com/sharedfiles/filedetails/?id=2643985164

https://steamcommunity.com/sharedfiles/filedetails/?id=2434836833