Rewriting Physics:

Levitite:

The substance that makes this whole world possible. It is incredibly useful, but too abundant to be expensive. Rich veins of levitite are found in all land masses. Trace amounts are also found in loose ground, water, and plant life. As the name suggests, this strange element keeps the continents afloat.

It is immune to the effects of gravity and reacts in a magnetic manner to positive and negative energy. In a neutral state, a chunk of levitite will float midway between the core and the outer ring, on the same level as shell 3. When infused with negative energy, it will sink closer to the closer. With positive energy, it will float up.

Levitite loses its charge over time. Greater concentrations are better able to hold a charge. Avatars are regularly infusing their home shell with the requisite energy to keep its orbit stable.

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