The flow of all thought and intention across Alaria. The Psywinds are currents of flowing Ezz that carry the mental activity of every living being within the planar stack. Those thoughts pass through all things, connecting mind to mind across any distance.
What the Psywinds enable
The currents do several kinds of work at once. Creatures attuned to them speak mind to mind without sound. Syncopaths perceive and stir the Psywinds without pause, unable to look away. Prayer crosses through them: a daemon in Celestia hears its worshippers because their calls travel the Psywinds to reach it, and during an active ritual the channel runs both ways, so the daemon can reach back across the same currents to guide a working performed in its name. True names ride the currents too, which is why a name spoken anywhere on Alaria can be heard by the one who holds it. And psy magic draws its power straight from this flow.
Substance
The Psywinds are made of flowing Ezz, the universal substrate that holds both Azus's order and Melera's randomness. After the Ezz Rift flooded Alaria, they became the medium through which spirit-bearing creatures could think, intend, and connect at all.
Because the Psywinds are flowing Ezz, they carry whatever the Ezz carries. When the substrate was poisoned during the Blight of Arcanus near the end of the Lost Ages, the Psywinds carried that death-resonance into every mind and working that drew on them, and tapping them killed outright until the contamination passed. The currents did not cause the Blight. They were the channel that delivered it.
Counterpart: Faesong
The Psywinds and Faesong are the two great ambient magical forces in Alaria. The Psywinds carry thought and intention, flowing between all minds, generated by the mental activity of every living being. Faesong carries emotion and harmony, flowing outward from Melera as a constant melody under all creation. Where the Psywinds are heard as whispers and images, Faesong is felt as harmony or dissonance. Telepaths and psy mages work the Psywinds; druids and fae attune to Faesong.
They are not two separate forces. They are two faces of the same Ezz, the substrate Azus and Melera made together, equal parts thought and emotion. The Psywinds are the thought-face, Faesong the emotion-face. A being who could perceive both at once would perceive the full current of Ezz itself.
The Psywinds and psyic energy
Psyic energy fills the space between the planar layers of Alaria. It is the omnipresent substrate through which the Psywinds flow. With practice or natural talent, it can be harnessed to work psy magic.