Naiads are the nymphs that fell in love with a river, lake, waterfall, or pond. They are excellent swimmers, and with time, they will know every pebble in their territory.
Despite this, they are not territorial like the dryads.
They love exchanging their treasures for new treasures.
If you throw a coin into a naiad’s water and make a wish, it won’t come true, but they will probably pop their head up and give you something in return. Perhaps a pebble or perhaps a true treasure.
Naiads don’t have much magic on their own, they can control a bit of water, enough to reach out and bring the lower hanging fruit to them, but when in groups, they can summon storms and they love doing so.
The wind blows all sorts of new treasures into the water and when floods happen, they see their territory expanded.
There are a few naiads who reside inside cities within fountains. Those naiads collect the coins and give them to the guards who collect them each morning. In exchange, not only is there fountains kept pristine clean, but the monarchy is slowly building underground water tunnels for the naiads to expand their territory without floods and allowing deliveries between fountains.