Never released Lego Monorail - The Seatron theme that never was

I just found out that there was a 4th Monorail set which was NEVER RELEASED !
It was from a planned Seatron theme, a space sub-theme, set on a sea planet.
Once I'd found out, that was it, I had to find out everything there is to know...
You can.watch The Atlanta Brick Co's video here: • Remaking SEA-TRON! The...