C.O.G.

Innate Spellcasting. The C.O.G.'s innate spellcasting ability is Intelligence (spell save DC 20). It can innately cast the following spells, requiring no material components:

At Will: Minor Illusion, Prestidigitation,  Detect Magic, Silent Image, Vicious Mockery, Identify, mending

5/day: Confusion, Dominate Person, Modify memory, counter spell, dispel magic, fear, Major Image

1/day: teleport, feeblemind

Multiattack. The armor makes Six melee attacks or two special actions.

Mechanical Fist. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 13 (2d6 + 7) bludgeoning damage. For every 40 health lost, one arm is decommissioned, revoking their attacking.

Upload Cable. Long, sharp cables attached to the bottom of the C.O.G. reach out to attempt to upload a creature. +10 to hit. Hit: (1d4 + 7) piercing damage. Creature must make a intelligence save DC 20 or be stunned until the cable is removed or they beat the save. If the cable is still within the creature by the next turn, they take an additional 20 (10d4 psychic damage). If a creature dies while attached to this or is targeted after death and their brain is undamaged, the creature is added to the collective and can't be revived unless under the means of a wish spell. A successful upload recovers 20 health. 

Screen Slayer. (Recharge 3-4)The large screen starts flashing different colors and images, indoctrinating creatures onlooking. Creatures make a will save DC 18. On a fail save, creature is blinded for a turn and takes 34 (3d12+ 10) psychic damage. On a pass save, target takes half damage. 

Analyze. Scan over an enemy within sight. Has advantage on hitting said target next attack. Enemy has disadvantage attacking the user this turn. 

Divide By Zero. (recharge 4-5) Formulate a confusing ongoing pattern of arguments flashing at enemies. Enemies make a DC 18 will save. On a fail save, they subtract 2d4 intelligence from their score. On A Pass, they are unaffected. Creatures with an intelligence below 6 are unaffected by this move. 

Collective Escape. At any point, the head of the C.O.G. which hosts the collective crystals can split off and rocket away at double movement speed. It abandons it's body which explodes for 70 (10d12+10) fire damage in a 60 foot circle. The head however has no way of attack and can't use any reactions or legendary actions besides Legendary Resistance. The C.O.G. has no other options but to run away. The C.O.G. must have at least 40 health to use this ability. It will attempt to reconstruct itself in a 2d12 months. 

C.O.G. can take 3 legendary actions.

Legendary Resistance

Voice of the Collective- Enemy makes a intelligence save of DC 25. On a fail save, enemy creature takes 17 (2d6+10) psychic damage and have disadvantage attacking the C.O.G. 

Relocate Fly 60 feet away without provoking attack of opportunity.