Universal Transportation Ship is the most primitive technology to be able to cross Universes, which can be constructed by sub-Multiversal civilizations with basic Imaginary Transfutation skills. You can find these ships at Nexus Cubes, or the construction site from any Imaginary Cubes.
This ship can zoom across Universes in minutes on general usages. And at peak, it can go ~ 27.05 trillion ly/second, around 3.907 Quettameters per second. It can also go as slow as 10 feet per hour, so it makes a great commercial vehicle, being only as big as the average plane.
Structure[]
Although, all post-universal transportation ships are cuboid, it is a cube! It also comes with a bathroom, being the best part. At least until Cetaversal Transportation Ship.