Boogeyman

Terror Aura. All hostile creatures that start their turn within 20ft of the Boogeyman must make a wisdom saving throw DC 13 and if they fail they are frightened and while frightened this way they are stunned. They can repeat this saving throw at the end of each of their turn if they are frightened.

Feed Off The Fear. When the Boogeyman has a creature frightened of them for one week the Boogeyman increases by 1 CR. When this happens the Boogeyman gets an extra 4 + constitution modifier maximum HP, every three levels the Boogeyman increase by one size giving at an extra +10 and +1 to AC, the Boogeyman has an extra 5ft range every 6 levels, every two levels the Boogeyman learns new spells as shown on the table, every two levels the Boogeyman gains an additional spell slot in every level spell that is below its highest level spells (cap of 8-spell's level minimum of one), every time the Boogeyman levels up they gain an extra +1 to all ability score they have to a cap of 24 per stat, every five levels the Boogeyman gets an extra 5ft movement speed, and the Boogeyman get more abilities that are listed later on in the stat block. 

Shadow Crawl (CR 7). When the Boogeyman is in darkness they can sink into the darkness (no action required) granting full cover also granting them triple movement speed while in the darkness. However while in the darkness they can only move and they cannot be harmed while in the darkness. The Boogeyman can also only move in darkness, if they enter dim light or bright light they are immediately expelled from the floor. While moving in the darkness they can move along the walls or roof. At CR 12 the Boogeyman ignores the dim light requirement. 

Hive Matter (CR 10). While in their lair the Boogeyman can designate a space that can be up to 500ft large inside of their lair over the course of an hour, (this can be up to 60ft tall too). This area is living and is described in the lair actions. The area in the Hive Matter is difficult terrain and the Boogeyman knows when a creature is in the area of Hive Matter, the Boogeyman also has actions that it can only use while inside the Hive Matter (listed in actions description). A creature that is unconscious in or restrained by the Hive Matter for a minute it embedded in the Hive Matter until a creature spends their whole turn to tear them from the Hive Matter. A creature that is trapped in the hive matter is frightened by the Boogeyman, stunned, paralyzed, and unconscious. A creature that is trapped in the Hive Matter for a day either is permanently frightened of the Boogeyman or has their hitpoint maximum halved by the Boogeyman. A creature that is trapped inside of the Hive-Matter for week turns into a Boogeyman that is controlled by the Boogeyman who made the Hive-Matter.

Aversion To Light. The Boogeyman when in dim light has halved movement speed, disadvantage on all rolls, and vulnerability to fire and radiant damage. However while in bright light the Boogeyman is vulnerable to fire and radiant damage, takes 6d4 radiant damage at the beginning of each of turn inside of the Bright Light, and will spend the end of each of their turns using all of their movement speed running away from the light. At CR 10 the Boogeyman is not affected by dim light and only by bright light.

(CR 16 Only) Legendary Resistance (1/Day): When the Boogeyman fails a saving throw it can choose to succeed instead. The Boogeyman gains another Legendary Resistance at CRs 20, 25, and 30.

Aggressor. The Boogeyman has advantage on attack rolls and does double damage when attacking creatures that are frightened of it. 

Spellcasting. The [Boogeyman] is a 3rd-level spellcaster. Its spellcasting ability is [charisma] (spell save DC 13, +5 to hit with spell attacks, at CR 7 the Boogeyman can cast Disguise Self and Dissonant Whispers at will, at CR 10 the Boogeyman can cast Tasha's mind whip and Invisibility at will). The [Boogeyman] has the following spells prepared:
Cantrips (at will): [Minor Illusion], [Encode Thoughts], and Prestidigitation. 

1st level (4 slots): [Cause Fear], [Dissonant Whispers], and Disguise Self.

2nd level (2 slots): Tasha's Mind Whip, Darkness, and Invisibility.

(CR 5) 3rd level (2 slots): Enemies Abound, Fear, and Hypnotic Pattern.

(CR 7) 4th level (2 slots): Shadow Of Moil, Hallucinatory Terrain, and Phantasmal Killer

(CR 9) 5th level (2 slots): Seaming, Synaptic Static, and Telekinesis.

(CR 11) 6th level (1 slot): Mental Prison, Summon Fiend, and Mass Suggestion.

(CR 13) 7th level (1 slot): Power Word Pain, Teleport, and Finger Of Death.

(CR 15) 8th level (1 slot): Maddening Darkness, Reality Break, and Dark Star.

(CR 17) 9th level (1 slot): Time Ravage and Weird

Multiattack.(Unlocks at CR 5) The Boogeyman makes two claw attacks one of which can be replaced with a Focus Fear attack. This turns two four claw attacks at CR 10 which up to one can be replaced with a Focus Fear attack or a Terror Blast if available. At CR 15 this turns two three claw attacks and three bite attacks two of which can be replaced with a Focus Fear attack or a Terror Blast if available. At CR 20 this turns into four claw attacks and four bite attacks three of which can be replaced with a Focus Fear attack, a Terror Blast if available, or three uses of spellcasting.

Claw. Melee Weapon Attack: +7 to hit, reach 10 ft., 1 target. Hit: 9 (2d4 + 5) [slashing] damage. On a hit the target is frightened of the Boogeyman until the end of the Boogeyman's next turn. 

Bite (CR 15 only). Melee Weapon Attack: +12 to hit, reach 10ft., 1 target. Hit: 19 (2d12+7) [piercing] damage and 13 (2d12+7) psychic damage. The Boogeyman regains an amount of hitpoints equal to the amount of psychic damage dealt.

Focus Fear. Ranged Spell Attack: +5 to hit, range 10/100 ft., 1 target. Hit: 9 (2d6 + 3) [psychic] damage and target is frightened until the end of the Boogeyman's next turn. Alternatively the Boogeyman can just frighten the creature and keep that creature frightened for as long as the Boogeyman wants, however the Boogeyman can only do this to one creature at a time and must concentrate on it as if concentrating on a spell.

Terror Blast (Unlocks at CR 10) (Recharge 5-6). When this is used all creatures within 100ft of the Boogeyman they must make a wisdom saving throw and if they fail they take 8d6 psychic damage and are frightened for one minute. If they succeed they take half damage and are not frightened. At CR 20 the damage turns into 16d6 psychic damage and recharges on a 4-6. At CR 30 this damage turns into 16d8 psychic damage and imposes disadvantage on the saving throw. 

Summon Tendril (Hive-Matter area only). While inside of the Hive-Matter the Boogeyman summons a large sized Tendril within any unoccupied space inside of the Hive-Matter. The Tendril has an AC of 16 and an amount of hitpoints equal to 5 times the Boogeyman's CR. The Tendril has an initiative of 18 (losing ties) and has the following actions, it also has a 15 movement speed. The tendril has no CR and has an 18 for strength, dexterity, and constitution but has a 1 in all other stats. It also uses the Boogeyman's proficiency bonus. The Boogeyman can only summon 1Tendril at a time. 

• Slam. Melee Weapon Attack. +8 to hit. reach, 15ft. 1 target Hit: 16 (4d6+4) bludgeoning damage, target is then grappled (escape DC 16) while a creature is grappled they are restrained, while a creature is grappled this way the Tendril cannot make any more Slam attacks.
• Crush. 1 grappled creature. While the Tendril has a grappled creature they can do 20 bludgeoning damage to them. Alternatively this can be 40 non-lethal bludgeoning damage knocking them unconscious if they are knocked unconscious.
• Embed. Reach 15ft, If the Tendril has a creature grappled and can reach a wall inside of the Hive-Matter the Tendril can embed the creature inside of the wall. While embedded in the wall they are grappled and restrained (escaped DC 18). Look at Hive-Matter special trait while creature is embedded this way. 

Sleeping Spores (Hive-Matter area only). The Boogeyman makes a 30ft large cube in an area within the Hive-Matter, this cube goes away at the end of the Boogeyman's turn. Once this is made all creatures must make a constitution saving throw DC 16, creatures that fail are unconscious. 

Spike Trap (Hive-Matter area only). The Boogeyman makes a 10ft wide cube inside of the Hive-Matter that goes away after a minute. Creatures that are in the area when its made take 2d8+7 piercing damage and have their movement speed reduced to 0ft because the spines keep them stuck to the floor. At the beginning of each of their turns a creature stuck this way can make an acrobatics or athletics check DC 16 regaining their movement speed on a successful check. Creatures that move through this space takes the damage and has their movement speed reduced to 0ft until they succeed the check. 

(CR 30 Only) Scared To Death. The Boogeyman does 47 (10d8+7) psychic damage to all creatures within 30ft of it. This damage is halved if  the targets succeed a DC 21 wisdom saving throw. If they fail they take the damage and they are aged by 2d8+2 years, every 9 years a creature is aged they level up and if they exceed the normal lifespan of their race's lifespan they will die and can only be brought back by the True Resurrection spell or the Wish spell. This aging can go away if they are put under the effects of the Greater Restoration and take a Long Rest after being put under the spell's effects.

Darkness Shroud. When this is activated all spaces within 5ft of the Boogeyman are shrouded with magical darkness and if a creature is in this and can't see through it they are frightened of the Boogeyman, this can also be deactivated during the Boogeyman's turn with no action required. Every five levels this area increase by 10ft.

These are unlocked at CR 10. The Boogeyman has one legendary action and can use these at the beginning or end of any creature's turn other than its own. These recharge at the beginning of its turn. At CRs 15, 20, 30 the Boogeyman earns another legendary action. 

Shadow Warp. The Boogeyman can only do this while in dim light or darkness. The Boogeyman teleports from one dim light or dark space into another unoccupied space within 100ft of it that is also in dim light or darkness. 

Claw. The Boogeyman makes a claw attack against a creature within its range.

Cantrip. The Boogeyman casts a cantrip.

(CR 15 Only) Focus Fear. The Boogeymans uses its Focus Fear Attack. 

(CR 15 Only) Illusory Clone (Costs 2 Actions). The Boogeyman makes a clone of itself that has the same stat block as this Boogeyman but only has one hitpoint and a 10 AC. This Boogeyman is summoned in an unoccupied space within 60ft of them. This clone can make attacks and has an initiative of 10 losing all ties.

(CR 20 Only) Phobiac Maniac (Costs 3 Actions). The Boogeyman uses its Terror Blast even if it doesn't have a use left. If it uses this without expending the charge they take 18d6 damage that cannot be reduced in any way.

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