You can breathe both air and water indefinitely. This ability reflects your Zulathún physiology, which allows for natural aquatic respiration through gill-like structures and semi-permeable membranes. You suffer no penalties for being underwater and can act as if on land.

You can telepathically communicate with any creature within 30 feet of you that understands at least one language. This communication takes the form of sibilant whispers, surreal images, or echoing emotions that reverberate in the mind. You do not need to share a common language, but the creature must understand a language to receive your message. This trait does not allow the creature to respond telepathically unless it has a similar ability.

As a bonus action, you can lash out with a tentacle of psychic energy at a creature within 15 feet. You make a melee spell attack using your Charisma modifier. On a hit, the target takes 1d8 psychic damage and must succeed on a Strength saving throw (DC = 8 + your proficiency bonus + your Charisma modifier) or be pushed 10 feet away from you. This movement does not provoke opportunity attacks.

You can use this trait once per long rest. At 5th level, you can use it twice per long rest.

Your exposure to the pressure and madness of the deep has strengthened your mind.
Once per long rest, when you make a Wisdom or Charisma saving throw, you can add 1d4 to the result. You must decide to use this feature before knowing the outcome of the roll.