Mothman

Mothman CR: 6

Large aberration, chaotic neutral

Armor Class: 17

Hit Points: 156

Speed: 30 ft

STR

13 +1

DEX

15 +2

CON

14 +2

INT

14 +2

WIS

17 +3

CHA

9 -1

Saving Throws: Wis +5 Dex +6 Con +4

Skills: Electrical Interference. The mothman’s potent psionic energies create a roil in the air, disrupting the senses of mortal creatures and causing metal to behave erratically within 100 feet of it. Any creature within the aura and wielding a heavy weapon made of metal takes a -2 penalty on attack rolls. A creature wearing heavy metal armor within the aura reduces its speed by half. In addition, the mothman is immune to magic missile.

Evasion. If the mothman is subjected to an effect that allows it to make a Dexterity saving throw to take only half damage, the mothman instead takes no damage if it succeeds on the saving throw, and only half damage if it fails.

Flyby. The mothman doesn't provoke opportunity attacks when it flies out of an enemy's reach.

Foresight. The mothman can’t be surprised and has advantage on attack rolls, ability checks, and saving throws. Additionally, other creatures have disadvantage on attack rolls against it. Unlike normal, if an attacking creature would have advantage twice or more (such as from true strike while making a melee attack against a prone mothman) the attacking creature has advantage.

Damage Vulnerabilities: Fire, Lightning, Thunder, Acid

Damage Resistances: Psionic, Psychic, Cold

Condition Immunities: charmed, frightened

Senses: The mothman has heightened hearing and vibrational sense. His eyesight is limited in bright light situations including daylight.

Languages: Infernal, Abyssal, Deep speech

Challenge Rating: 6

At will: Detect Thoughts, Confusion, Darkness, Dispel Magic, Thunder wave.

1/day: Phantasmal Killer - 4th Level illusion - Wis spell save DC 16

2/day: Crown of Madness - 2nd Level Enchantment - Wis Spell save DC 16

Actions

The Mothman can attack with it's talons. 2X attacks +7 to hit, slashing damage.

Legendary Actions

Crimson Gaze - When a creature the mothman can see rolls a 20 on a D20 for an attack roll, ability check or saving throw, the mothman can make them reroll the die and use the new roll instead.

This creature has enormous dusty wings and a bipedal body made of dark chitin. It's head is oversized with huge circular eyes that glow red when active.

Basic Information

Anatomy

At the beginning of the battle the Mothman will burst into five copies of itself which hover around. The copies are constructs with 30 HP. Not even Mew will be able to tell which is real due to the electromagnetic interference in the air.
Attacks against the Mothman with anyone wearing metal armor take a -6 penalty. (Exceptions Hops' hammer which is constructed from a magical substance.)
When the Mothman attacks anyone wearing metal armor they need to do a DC 15 Strength saving throw be knocked prone.
Spell concentration must be rolled each round. DC 15 Constitution save.
Escape Sneak Attack / Magnetic Hold / Reduce damage from metal weapons / Sonic screech / Spores and eggs planted around the Forlorn Tower.
Arm Blades do 2d12 +7 damage each

Additional Information

Perception and Sensory Capabilities

The Spores and Eggs - Some of the egg like protuberances scattered around the tower are unfertilized eggs which act as Magnetic ooze. The rest are fertilized eggs which will begin to spawn new Mothmen.
The Eggs act as Magnetic Oozes, very similar abilities. The Hatchlings have all of the base monster stats of the adult with none of the legendary or other abilities.  Eggs Lair Action :  The eggs emit a psychic Resonance that inundates anyone entering the tower. Roll a DC 18 Intelligence check or act as if under the influence of a crown of madness!