Gates of the Moon (Planescape)

From Karriviki

It is a misty realm, where the ever-present moon waxes and wanes, causing regular tides in the sea surrounding Selûne's palatial hall called Argentil as well as shifts in the personality of the inhabitants. The brighter the moon, the more happy, friendly, and stable the natives are. As the moonlight fades, the locals become sullen, withdrawn, and even angry or hopeless.