How to unlock stone coffin?

[Oski Unreal]

How to unlock the stone coffin.
I've already defeated bosses up to level 37.
I play, I build.
And I still don't have the stone coffin unlocked.
Only the wooden coffin.
What am I doing wrong or what am I not doing.
Help

[Suzaku]

The main quest line unlocks it. You should have gotten it already if you've built a base with stone walls and a ceiling. (I don't recall the exact quest that rewards it)

[aint2bright]

You get the blueprint for stone coffin after upgrading part of your castle to stone (don't forget the floors.)

[Carnatux]

do your quest line its part of it

[Xero]

You have to complete the quest called "Waygate". You have to build and interact with your first waygate ( teleport ). It unlocks the blueprint for the Stone Coffin.

Waygate Quest :
https://vrising.fandom.com/wiki/Waygate

To get the blueprint for the Waygate, you have to complete the quest "Building a Castle".

Building a Castle :
Complete a Castle room by laying down floors and building surrounding Castle Walls to generate a roof. Palisade walls do not count.

Scroll down to the middle of the All Quests link and you'll find both quests.

All Quests :
https://vrising.fandom.com/wiki/Journal