Lunia, the Silver Heaven, is the first layer of Mount Celestia, and the closest to the Astral. All portals into the Mount from the Astral, the Outlands, Bytopia, or Arcadia lead to this layer, dumping their travelers in the Silver Sea, a vast endless ocean of holy water that laps at the shores and provides not only a defense against fiendish forces that may otherwise think to invade, but the first exposure to purity for those seeking to enter the plane. It holds harm only for those that truly seek ill will against the plane, however. For other travelers, any number of sea dwellers keep ready to rescue those not expecting or accustomed to the water, including communities of aquatic elves or dolphins, the occasional passing balaena, and the native zoveri, ensuring that none drown in the Sea for want of aid.
The skies of Lunia are a perpetual moonlit night, an eternal cusp of twilight dotted by twinkling, silvery stars, the glittery light of Mercuria shining down on the land below and the wonder of Chronias occasionally visible through the shifting clouds; to many, the skies of Lunia are reminiscent of the Astral itself. While the layer is dominated by the Mount itself, it's surrounded by a number of islands each with their own smaller peaks. On these islands can be found a number of citadels and villages, each in their own styles and architectures befitting their varied cultures, with occupants whose acceptance of outside travelers varies from total isolation to total welcoming.
As the first layer, Lunia is where one finds the majority of travelers or settlers from outside the plane, and as a result it has the most varied population; here, a person can find those here simply to dwell in the shadow of the Mount, those first beginning their paths up its slopes, and those seeking the first glimmers of atonement. The most common natives to be found here are the ubiquitous lantern archons — the lowest ranked petitioners of this plane, floating balls of light seeking to improve themselves and move further up the Mount. Most other natives are found further along the slopes, but there are more than a few lammasu, noctrals, or hollyphants dwelling about.
- Manual of the Planes, pp.134
- Planes of Law - Mount Celestia, pp.12-15