This is Spectral, a mod I've been working on for a while. It adds several things, all with the focus of shifting/being only visible/tangible for certain entities. Currently, it adds the Spectral Block, Spectral Goggles, and Spectral Dust, all with crafting recipes. The Spectral Block is an unsual block, which can only be collided with and seen by Spectral entities. Spectral Goggles allow you to turn yourself Spectral as long as you wear them Spectral Dust allows you to either eat it to become temporarily Spectral, or apply it to other mobs to turn them Spectral Spectral entities cannot see or interact with non-Spectral entities, and vice-versa. More features will come soon!