Some magical creatures possess the ability known as Tongues, allowing them to understand and be understood by all languages. When a being chooses to use this ability to speak, their voices sound otherworldly and impossible for plain mortals to replicate. Their communication transcends language barriers, connecting with the essence of understanding. Anyone intellectually capable of understanding language can understand someone speaking in Tongues. Examples of creatures who speak in Tongues include Anx and Dymarnians.
Some mortals can end up with this ability as well. When a mortal has this ability, it's not "always on" as it is for immortal magical creatures. They have to focus and choose to use it. Examples of mortals that might have this ability are Anxlings and Moonkin.