Well, i've been a lego fan when i was young, now playing lego with my daughter have reawakened the lego flame :)
I like submarine, space, sci fi, and it has started like a defi with my child, first on lego 3Ddesigner.
The submarine have a lot of functions, periscope, sealed door, diving room, cargo bay with hull door, hydrogen propulsion, gear box driving both propeller and vertical reactor, torpedo room with 4 tubes, laboratory with medical bay, inner cranes, bow and stern hatches.
My inspiration came from Jules vernes 20000 under the sea and league of extraordinary gentlemen nautilus, and all i wanted to see in my submarine.
Three detachable parts and each roof can be removed for playing.
Close to 2500 pieces.
So i let you have a look and perhaps enjoy. My daughter and i will read your comments with pleasure, answer to your possible questions.
(soon i will publish my space tank)