A new bio-base builder tool similar to the bioscanner. This would allow you to build bases on passive leviathans. You could have a base in a deep wing brooder, or maybe a new leviathan similiar to the vent garden could even have a benefit like making plants grow faster. You would be able to use a new base part called “The Helm” (or something similiar) to semi-control the leviathan. The Helm might also be a good new use for Plasteel (as it only has like 2 uses right now) and take plants that you can harvest to use, maybe different plants would have different amounts of control based on the leviathan.