Ika-ika

Also known as the fishfolk, the god-makers, and "those annoying slimy folk", depending on location. One of the oldest people, these appear to be short (~4'-5' tall), purple-skinned (with slimy skin) humanoids with webbed feet and hands and fish-head-like faces featuring bulbous, wide-set eyes and pointy peg-like teeth. Despite their appearance, they are amphibious, although they require water to keep their skins moist and reproduce underwater (via laying clutches of eggs).

The ika-ika are one of the older races, dating back to sometime in the 2nd Age. Their origin is uncertain, but it is believed that Leviathan or its agents created them out of goblins, hybridizing them with fish. They lack the shared-memory-space of the goblinfolk, and instead have an unnaturally-large ability to believe. Given enough concentrated belief, the thing believed in can become real, at least to some degree. This happens primarily with "gods", where a group of ika-ika find some shiny idol-object and venerate it, creating an astral reflection of that thing that then empowers them (as pact-bound). None of these are very strong, since most ika-ika are also relatively easily distracted to the new shiny. When faith collapses, so does the believed-in creation, at least if it doesn't have an external source of support.

It is believed that this trait was observed and used as the basis for the Third Wish, allowing the faith of other creatures to have a similar (if more muted but more permanent) effect.