As a kid, two things obsessed me, space and dinosaurs. I had more books on these two subjects than anything else. Even today, I still enjoy both subjects, but it was especially exciting for me when sometime in the early 1990's, I discovered Tomy Zoids. The combination of science fiction and dinosaurs was a gift to me and especially when I discovered that they all included a tiny seated golden astronaut like pilot, I was hooked.
The extra special draw was the inclusion of sea borne creatures in the line, such as the 'Hammerhead' shark and the coelocanth-like 'Wardick' armoured fish. With clockwork motors inside and floats in the body, they work as well in water as on land, wriggling realistically along.
Disney's animated feature 'Atlantis' also featured biomechanical creatures such as the 'Ketak' fish and the wonderful Mike Mignola designed 'Leviathan', seen here in an earlier related post.