Marids are the water based version of genies (with Efreet as fire, Djinni as air and Dao as earth) and in classical mythology are thought of as the most powerful of the genies. They match the other genies in D&D mythology though, with some especially powerful ones (padishah) that may act as rulers. Rulers that don't especially get listened to because marids like to do their own thing, whether it's chilling in a palace, gathering pearls or capsizing ships. Honestly, it kinda sucks to be the padisha sitting on the Coral Throne, since the other marids really want that throne.
Like other genies, marids have a number of magical abilities, some of which are tied to their element, and are able to grant wishes if compelled to, a mood which can last a very short time since they're quite fickle beings.
Post somewhat late due to job responsibilities and being in Spain with my folks for the past week. It is crazy hot down there. My grandma hit the big 9-0 last weekend, though it's surprising how little she shows her age. It was a lovely celebration with absurd amounts of food. Feliz cumple, abuela.