Small fiend, monstrosity, any evil alignment

Armor Class: 10

Hit Points: 68 (8d6 + 40) 8d6+40

Speed: 30 ft , swim: 30 ft , climb: 30 ft

STR

10 +0

DEX

10 +0

CON

20 +5

INT

6 -2

WIS

7 -2

CHA

1 -5

Saving Throws: DEX +3 1d20+3 ,CON +8 1d20+8

Damage Immunities: Acid, Force, Psychic, Thunder; Bludgeoning, Piercing, and Slashing from nonmagical attacks

Condition Immunities: Blinded, Charmed, Deafened, Frightened

Senses: blindsight 300 ft. (blind beyond this radius), passive Perception 14

Languages: Understand Void Speech

Challenge Rating: 7

Proficiency Bonus: 3

Actions

Multiattack: The The Blind One makes three claw attacks.
Bite: Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 7 (1d4 + 5) 1d4+5 piercing damage. On a hit, the creature is grappled by The Blind One.
Claw: Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 10 (1d10 + 5) 1d10+5 slashing damage.

Bonus Actions

Echo Locate: The Blind One uses its echo location to identify all targets around it. Until the start of its next turn, The Blind One gains a +10 to its attack roll.
Confuse: The Blind One uses its echo ability to confuse any enemy around it that can hear it. All creatures it targets within its blind sight must make a DC 19 CON save. On a fail, the creature must roll a d8 when making an attack. On a 2-7 the attacker is unable to make the attack. On a 1, the attacker makes the attack against a target within range that The Blind One decides. On an 8, the attacker makes the attack as normal.

Reactions

Reactive: The The Blind One can take one reaction on every turn in combat.
Acidic Splash: As a reaction to getting hit with a melee attack, The Blind One deals acid damage equal to half the damage it took to its attacker.
Growth: When The Blind One uses its Drain ability, if it has all its hp, it can use its reaction to temporarily raise its hp and max hp by half the damage dealt. The Blind One keeps its new HP until either it is killed, or takes is dealt fire damage. When killed, its max HP is dropped to its normal max hp, when taking fire damage, its max hp is reduced by the damage taken until its max hp is back to normal.