The Nucleus resides at the very center of the Magical Nexus - the intersection of multiple worlds and whims. Another of the Stair Shaper's creations, this Structure serves as a conduit of the Magical energies that accumulate as more Monsters are Transposed to the Nexus. It's able to accomplish this by absorbing their energy signatures and converting them into a tangible form. If its shape looks familiar, that's because the diverse Star Rocks of the Monster World are actually the Stair Shaper's handiwork as well; left behind as monuments to 'first contact' and obtainable only through Starpower, the essence that amasses when harmonies from differing worlds are sung.