Beholder Silhouette

Normalization Cone. The beholder's central eye creates an area of normalization in a 30-foot-cone. Any creature, object, spell, or effect within the radius of the cone loses any modifier, bonus, or penalty that would be added to any attack roll, saving throw, ability check, spell save DC, or damage roll. At the start of each of its turns, the beholder silhouette decides which way the cone faces and whether the cone is active. The area works against the beholder's own eye rays. 

Silhouette.  The construct does not require air, food, or water. 

Proficiency Die. The construct is an imperfect replica of a Beholder. As a result, it is neither good nor bad at anything. Instead of a proficiency modifier, the Beholder Silhouette gets a Proficiency Die. When ever you roll an Attack Roll, Saving Throw, or Ability Check in which you would add your proficiency modifier, instead roll 1d6 and add it to the result. If you would not normally add your proficiency modifier, add 1d4 instead. Add 1d4 to all bite damage rolls.This damage is not affected by a Critical Hit, and is treated as the modifier to the damage, not a damage die.

Volatile Existence. As an imperfect replica of a Beholder, there are flaws in it's design. These imperfections cause it's body to fail on occasion. Whenever the silhouette rolls a natural 1 on any ability check, attack roll, or saving throw, it takes 1d6 damage. This damage is consider to have no damage type and can not be increased or decreased by any means. The silhouette also fails the roll, even if they would have succeeded otherwise.

Bite. Melee Weapon Attack:  1d6 to hit, reach 5 ft., one target. Hit: (2d6 + 1d4(not affected by a critical hit)) piercing damage.

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

1: Ability Ray : The target must make a DC 10+1d6 Constitution saving throw or have a random ability score set to 10. This effect can only be removed by a long rest or a Greater Restoration.

2: Skill Ray : The target must make a DC 10+1d6 Intelligence saving throw or gain a penalty modifier to a random skill equal to their Proficiency Modifier. If the target has Proficiency in this skill, this effect can stack up to twice on this skill. If the target has Expertise in the skill, this effect can stack up to three times on this skill. This effect can only be removed by a long rest. Alternatively, you can target one instance of this effect to remove with a Greater Restoration.

3: Saving Ray : The target must make a DC 10+1d6 Wisdom saving throw or gain a penalty modifier to a random saving throw equal to their Proficiency Modifier. If the target has Proficiency in this saving throw, this effect can stack up to twice on this saving throw. If the target has Expertise in this saving throw, this effect can stack up to three times. This effect can only be removed by a long rest. Alternatively, you can target one instance of this effect to remove with a Greater Restoration.

4: Martial Ray : The target must make a DC 10+1d6 Dexterity saving throw or gain a penalty modifier equal to their Proficiency Modifier to the weapon last used in an attack. If the weapon can't gain any more penalty modifiers, the effect goes to a random weapon. Unarmed attacks count as weapons, as do natural weapons such as claws or horns. If the target has Proficiency in the affected weapon, this effect can stack up to twice on this weapon. This effect can only be removed by a long rest. Alternatively, you can target one instance of this effect to remove with a Greater Restoration.

5: Armor Ray : The target must make a DC 10+1d6 Strength saving throw or lose Proficiency with their currently equipped armor. If the the target has both armor and a shield, randomly choose one. If the target is not wearing armor that they have Proficiency with or is not using a shield with Proficiency at the time they are targeted, they instead take 1d10 force damage. This effect can only be removed by a long rest. Alternatively, you can target one instance of this effect to remove with a Greater Restoration.

6: Uncertainty Ray : The target must make a DC 10+1d6 Charisma saving throw or take 2d10 psychic and become Uncertain for 1 minute. An Uncertain creature has disadvantage on all ability checks and attack rolls and can only take an action or bonus action, but not both for the duration. They can repeat the saving throw with disadvantage on the end of each of it's turns.