Contemplator

Unbreakable Mind: Immeasurable years of contemplative thought have built up a staggering intellect within a contemplator. As a result, a contemplator adds its INT modifier to AC, and is immune to being Charmed, Stunned, or Frightened

Expert Tactician: The contemplator can not be surprised, and has advantage on any attacks of opportunity it makes.

Living Encyclopedia: The contemplator makes all knowledge checks with advantage, and whenever it rolls a knowledge check, the result of the die roll can not be lower than 10. If a die is rolled at 9 or less, it is considered a 10. The contemplator also adds double its proficiency bonus to any knowledge rolls it makes. 

Deflect Missiles. The contemplator may use its reaction to deflect or catch any incoming projectiles, provided it is small enough to do so. When a missile is deflected, the contemplator reduces the damage it takes by 15 (1d10 + 10). If the damage would be reduced to 0, as part of the same reaction the contemplator may throw the projectile as a ranged attack which uses the same modifiers and damage as one of its Slam attacks.

Not of This World. A contemplator doesn’t need to eat, drink, sleep, or breathe. 

Encase. Any target grappled by the contemplator’s manifested stone arms immediately encases the creature in a stone prison 1/2” thick. The stone cocoon has an AC of 20, and 10 HP. A creature trapped inside may make a STR save (DC 21) to break free from within. The encased victim can not use any weaponry or cast any spells that have somatic components to try and break free, as the stone prison does not allow enough room for movement. On a failed save, the stone prison tightens up as the contemplator senses its prisoner attempting to escape. This causes 7 (2d6) Bludgeoning damage, and prevents the creature from making another save for 24 hours.

Island Refuge. The contemplator values its privacy. A quiet place like a secluded island makes the perfect home, free from disturbances, where it may spend years at a time focusing on questions beyond mortal understanding.  So much does the contemplator value its privacy, that it will find a small island, or if none is available, create one from the stone at the bottom of the ocean, and attune to it. Once attuned to its island, the contemplator can use some form of primal locomotion to actually separate the island from the seafloor, keep it afloat, and travel at a rate of 25 miles each day. In order to do this, the contemplator must not take any other actions aside from focusing on the control of the island. In some cases, it is even possible for a contemplator to pull the island out of the sea and into the sky, where it floats in the air. If the contemplator's island is destroyed, it may attune to a new small landmass with no bigger than a 1/2 a mile radius over the course of 1 year.

Multiattack. The contemplator makes three Slam attacks.

Slam. Melee Weapon Attack: +13 to hit, reach 5 ft., one target. Hit: 19 (2d10 + 8) bludgeoning damage. The target must also succeed on a STR (athletics) check, or be knocked prone.

Arcane Bolt. The contemplator manifests a magical arcane bolt in its fist, and hurls it at the target. Ranged Weapon Attack: +8 to hit, range 120/600 ft., one target. Hit: 29 (6d6 +8) Force Damage.

One With Stone (1/Day). The contemplator may create up to 3 Huge stone arms, crafted from the very earth itself. They create stone arms that appear within 60 ft. of the contemplator. The stone arms take their turn during the contemplator’s turn, and have the following statistics: 25 Hit Points; AC 20, a reach of 10 ft., one slam attack (same as contemplator’s), and advantage on grapple checks. The arms can extend outward up to 50 ft. from their location to make an attack, before returning to their original position at the end of the contemplator’s turn. Any creature hit by an arm’s slam attack is grappled by the arm and subject to the Encase trait. All other statistics for saves and skill checks use the same bonus as the contemplator.

Intelligence Drain. Targets one creature currently under the effects of Encase. The contemplator drains knowledge from the captured creature, causing the victim to permanently lose 1 point of intelligence.  In order to use this ability, the contemplator must focus all its energy on absorbing the target’s mind. This process takes one full day, and if the contemplator is interrupted, or takes any other action, the intelligence drain is negated, and the contemplator’s 24 hour period of concentration must begin again. Once the affected creature’s intelligence score reaches 2 or less, the contemplator’s stone arm flings the now useless simpleton away from its lair. If the victim of the intelligence drain has its intelligence restored by a Wish spell, or similar magic, the knowledge fades from the contemplator’s mind. If the restored creature ever passes within 50 miles of the contemplator who lost the knowledge, the contemplator immediately detects them and will make every effort to intercept and attack the character. A contemplator can not tolerate knowing something, and then having that knowledge taken away. A contemplator who fully drains a wizard down to 2 intelligence points, gains knowledge of the spells that wizard had prepared, and is able to cast each of these spells once.

Optional Ruling: Drained Spells. Some contemplators have drained spells from powerful wizards, and have saved the use of those spells for times of crisis. A contemplator who has done this might have access to any spells you see fit. Be aware that these contemplators are much more dangerous, and pose a very significant threat.

A contemplator can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time, and only at the end of another creature's turn. The contemplator regains spent legendary actions at the start of its turn.

Teleportation (1 action). The contemplator teleports up to 120 ft. away from its current position into a space that it can see.

Shatter Thoughts (2 Actions). The contemplator claps his hands together, emitting psychic energy in a deafening blast. All creatures within 60 ft. of the contemplator must make a WIS save (DC 18) or take 14 (4d6) psychic damage. Anyone who fails this save by 5 or more is also Deaf for 1d12 rounds.

Witness The Cosmos. The contemplator makes a slam attack against a target that is within 5 ft. If the attack hits, the contemplator grabs the creature’s head and floods their mind with a near-infinite amount of knowledge. The creature must succeed on an INT save (DC 21) or be stunned for 1d8 rounds. The creature may attempt another save at the end of each turn to negate this effect. If the creature succeeds by 5 or more, they regain 1 expended spell slot of their highest level.