Some people ask me how to make walls like in my mod here's tutorial.
It's works with world portals

First of all you need to make wall witch will be stick, glue and...
So create a wall.










Now copy the wall and rotate it to make from it floor.












Now last step create linked_portal_door entity and place it in fornt of "walls"









If you don't know how to use linked_portal_door here are some tutorials:








In english :














In Polish :