From House of Hozz
Magic in TwinWorld is based on creating arbitrary connections between things. In essense, this means bending and re-assigning causality. Instead of you using the broom to sweep the floor, the stream outside uses the broom to sweep the floor. Instead of the wind blowing through the leaves, the wind plays music on enchanted instruments. This "system" allows enough freedom to do stuff, while being specific enough to allow creative story-telling.
Enchantment is most often used by the Fay.
For other kinds of Fay magic: See Life dust