Planar Tide

The phenomenon known as planar tide is the constant oscillation of the prime material plane, moving closer and further from the Feywild (Light) and Shadowfell (Dark) over the course of centuries. Catastrophes and disasters seem more common during the Dark planar tide, while the opposite is found during the Light planar tide. It is hypothesised that negative energy is more prevalent during the dark times, while positive energy during the inverse.