Blind beholder

Silence Cone. The beholder's central eye creates an area of silence, as in the silence spell, in a 150-foot cone. At the start of each of its turns, the beholder decides which way the cone faces and whether the cone is active.

Blindness. The beholder has disadvantage on checks that require sight, but it has advantage on checks involving sound and smell.

Critical weakness. If the beholder is hit with a slashing or piercing melee attack on it's under belly then it will instantly die.

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 14 (4d6) piercing damage.

Eye Rays. The beholder shoots three of the following magical eye rays at random (reroll duplicates), choosing one to three targets it can see within 120 feet of it:

• 1. Charm Ray. The targeted creature must succeed on a DC 16 Wisdom saving throw or be charmed by the beholder for 1 hour, or until the beholder harms the creature.

• 2. Paralyzing Ray. The targeted creature must succeed on a DC 16 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

• 3. Fear Ray. The targeted creature must succeed on a DC 16 Wisdom saving throw or be frightened for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

• 4. Slowing Ray. The targeted creature must succeed on a DC 16 Dexterity saving throw. On a failed save, the target's speed is halved for 1 minute. In addition, the creature can't take reactions, and it can take either an action or a bonus action on its turn, not both. The creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

• 5. Blinding Ray. The targeted creature must make a DC 16 Constitution saving throw, taking be blinded until the end of the beholders turn where they can make the saving throw again. On a failed save they remain blinded until there own turn where they can make the saving throw once more.

• 6. Telekinetic Ray. If the target is a creature, it must succeed on a DC 16 Strength saving throw or the beholder moves it up to 30 feet in any direction. It is restrained by the ray's telekinetic grip until the start of the beholder's next turn or until the beholder is incapacitated.

If the target is an object weighing 300 pounds or less that isn't being worn or carried, it is moved up to 30 feet in any direction. The beholder can also exert fine control on objects with this ray, such as manipulating a simple tool or opening a door or a container.

• 7. Sleep Ray. The targeted creature must succeed on a DC 16 Wisdom saving throw or fall asleep and remain unconscious for 1 minute. The target awakens if it takes damage or another creature takes an action to wake it. This ray has no effect on constructs and undead.

• 8.Infection Ray. The targeted creature must make a DC 16 Dexterity saving throw. On a failed save, the creature begins to turn grow black fungus around it's body and is restrained. It must repeat the saving throw at the end of its next turn. On a success, the effect ends. On a failure, the creature is begins to take 1d6 poison damage each turn until it succeds on it's saving throw.

• • 10. Eldritch Ray.  A three beams of crackling energy streaks toward a creature within range. The creature must then make a dc 16 dex save or take takes 1d10 force damage for each ray. The beholder can direct the beams at the same target or at different ones. It then makes a separate attack roll for each beam. If a target is hit by the eldritch ray then the beholder can choose to push them upto 10 ft away or 20 ft closer to itself.

The beholder takes 1d6 + 1 force damage for each beam every time it uses it's eldritch ray. The extra damage increases by +1 every time it chooses to use eldritch ray regardless of the amount of beams.

Echo location. After years of being blind the beholder has learned to let out screams to detect, nearby enemies.

The beholder can let out a low frequency scream in a 30 for cone then if any of those sounds hit a wall or nearby object then the sounds will bounce back giving the beholder a mental picture of what the area looks like. Any character hidden by a structure will not be detected. 

Turn head. If hit by a ranged attack the beholder can turn around pointing it's silence spell in the direction of the blast.

Final attempt. If a being gets within 5 ft of the beholder the beholder can point all of it's eyes at the target, then the target must make a dc 13 wisdom throw or become frightened. Then at the end of that targets turn if they are still in that spot, or have failed a dc 15 stealth check, while moving to another spot then the beholder will shoot the target with 1 of each of it's eye beams. It eyes will then become tired meaning that it won't be able to use any of it's eye beams for 1 minut.

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