Babel Fish King

The Babel Fish is a small, yellow, leech-like creature that inhabits the deepest swamps of the Underdark and probably the strangest thing in Toril. A being with an intelligence greater than or equal to 10 can attune to this parasite by inserting it into its ear and taking a long rest.

The Fish feeds on brainwave energy received from those around its wearer. It then excretes into your mind a telepathic matrix made up of mental frequencies and nerve signals that makes your brain vibrate in certain one.

The result is that you can instantly and continuously understand any form of language and speak and respond in the same one. After some minutes you lose the capacity of speaking a language if you're not currently speaking anybody that way because of the Fish is not excreting that frequency waves anymore

If the Fish remains for more than 1 week without receiving any brain frequencies other than those of its wearer the Fish dies and is destroyed with no possibility of resurrection.

Royal feces. The powerful and ancestral digestion of the Babel Fish King causes it to feed on even the tiniest waves of the surroundings which allows you to be aware of every living being around. This allows you to add his proficiency bonus to Perception rolls. Also you can't be surprised while you are conscious.

In addition, it also takes advantage of the unconscious waves around it, allowing you to cast Detect Thoughts 4 times a day. After the last charge is spent, you must take a long rest so as the Fish not to get indigested and regain all its charges.

Notes: Language: All, Proficiency: Perception, Control, Communication, Buff, Social, Utility, Combat, Sentient, Symbiotic