Using metaballs to create a tunnel, or sewer. Your interpretation! 
I’ve seen the tutorial earlier on Youtube and it’s great. Thanks
How is your game doing that you are working on?
Thanks!
Game’s going great, keep on my channel for updates and my website:
http://www.anythingbutroyal.com/
Just an idea -
You could add a lattice to the model instead of deleting the bottom half and retain some of the continuity from floor to ceiling rather than an abrupt change from one object to the other.
True! Good thoughts …