I decided to go with a quark star. It’s better than a black hole because we don’t even know if they exist. Perfect for expansion However, I still need something for him to be working on before he deals with the quark star. I’m looking not for a gadget or piece of tech. I’ve decided everything technological that we can think of, can be done. Speeders with deflector shields? Sure. We haven’t seen them but they can easily be done. I’m looking for something that would still be an emerging field of science. Something a Type II/III civilization would do next. Any ideas?