Solid-clouds

The general idea is nailed down, details are flexible.

Solid-clouds are the visible, locations of dense Aether. Solid-clouds are the most immutable substance in TwinWorld, since force against them results in merely passing through the mass. Their texture ranges from completely aetherial to the hardness of wet sand. (withstands impact, but allows for slow transmission). It is very difficult to discern the "density" visually, so walking on solid-clouds is quite treacherous. Sky Vines grow into, and from, solid-clouds.

Solid-clouds are most prevalant at the top origin of TwinWorld, since this is where the Aether originates. They tend to stick close up to the Outer Fire, protecting TwinWorld from its ravages. As they travel outward, they become more sparse, eventually disappearing altogether at the Horizon.

SolidClouds are impervious to all force, light, heat, and magic. They allow objects to pass through with enough force or time, have an independent temperature, scatter all light (hence their white color), and can not be affected by magic. However, they do amplify some magic (as Aether is an essential component in many spells) and some of the most powerful Fayrie casters live near the Solid-clouds.

Questions

• Perhaps Fairie Dust getting caught in clouds?
• Some animals burrow through Solid-clouds, no problem!