Elder Brain's Power

Your power over the mind of others has become comparable to that of an Elder Brain, granting you the following benefits:

Ability Score Improvement. Increase your Intelligence, Wisdom, or Charisma by 1, to a maximum of 20.

Blindsight. You gain blindsight out to a range of 120 feet.

Elder Brain's Expertise. You gain expertise in Insight.

Elder Brain's Telepathy. You can communicate telepathically with any creature within 1 mile of you.

Creature Sense. You are aware of the presence of creatures within 1 mile of you that have an Intelligence score of 4 or higher. You know the distance and direction to each creature, as well as each one’s Intelligence score, though you can’t sense anything else about it. A creature protected by a mind blank spell, a nondetection spell, or similar magic can’t be perceived in this manner.

Telepathic Hub. You can use your telepathy to initiate and maintain telepathic conversations with up to ten creatures at a time. You can let those creatures telepathically hear each other while connected in this way.

Elder Brain's Power. You learn the dominate monster spell. You can cast this spell without expending a spell slot. Once you cast this spell in this way, you can’t do so again until you finish a long rest. You can also cast this spell using spell slots you have. The spell’s spellcasting ability is the ability increased by this feat.

Psychic Link. As an action, you can establish a psychic link with one incapacitated creature that you can perceive with your Creature Sense feature. The creature becomes aware that something is linked to its mind once it is no longer incapacitated, and you can terminate the link at any time (no action required).
    The creature can use an action on its turn to attempt to break the psychic link, doing so with a successful Charisma saving throw (DC 8 + your proficiency bonus + the ability modifier of the score increased by this feat). On a successful save, the creature takes 3d6 psychic damage (the creature is aware that breaking the link will harm it). The psychic link also ends if you and the creature are more than 1 mile apart, with no consequences to the creature. You can form psychic links with up to ten creatures at a time.
    Until the psychic link ends, you can use your bonus action to perceive everything the creature senses or to return to your normal senses. While perceiving through the creature's senses, you are blinded and deafened to your own surroundings.

Sense Thoughts. As an action, you can choose a creature within 600 feet of you with which you have a psychic link. You gain insight into the target’s reasoning, its emotional state, and thoughts that loom large in its mind (including things the target worries about, loves, or hates).

Break Concentration. As an action, you can choose one creature within 120 feet of you with which you have a psychic link. You break the creature’s concentration on a spell it has cast. The creature also takes 1d4 psychic damage per level of the spell.

Psychic Pulse. As an action, you can choose a creature within 120 feet of you with which you have a psychic link. Each creature of your choice within 10 feet of the creature takes 3d6 psychic damage.

Sever Psychic Link. As an action, you can choose a creature within 120 feet of you with which you have a psychic link. You end the link, causing the creature to have disadvantage on all ability checks, attack rolls, and saving throws until the end of the creature’s next turn.