One thing holds consistent across the numerous worlds of science fiction and fantasy: everyone speaks the same language. Whether it's Lojban, English, Common, or the High Tongue of the Autumn Empire; there's one language that everyone knows, unless plot demands otherwise.
Do not gather and heap up and store for yourselves treasures on earth, where moth and rust and worm consume and destroy, and where thieves break through and steal. Matthew 6:19 KJV
The Lord of the Flies, the Muscimancer has studied magics that summon, control and otherwise deal with flies. The Fly Mage is an unwholesome character, also likely to have magics of disease, rot and pestilence up his sleeves. After fighting through his swarms of flies and his loyal acolytes and slaves, the Muscimancer reveals his final power, transforming into a giant half man half fly hybrid. He can fly, acid vomit, as well as continue to use spells, wield weaponry and command his swarms.