Amphibious. The hag can breathe air and water.
Innate Spellcasting. The hag's innate spellcasting ability is Charisma (spell save DC 12). She can innately cast the following spells, requiring no material components:
At will: dancing lights, minor illusion, vicious mockery
Mimicry. The hag can mimic animal sounds and humanoid voices. A creature that hears the sounds can tell they are imitations with a successful DC 14 Wisdom (Insight) check.
Claws. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) slashing damage.
Illusory Appearance. The hag covers herself and anything she is wearing or carrying with a magical illusion that makes her look like another creature of her general size and humanoid shape. The illusion ends if the hag takes a bonus action to end it or if she dies.
The changes wrought by this effect fail to hold up to physical inspection. For example, the hag could appear to have smooth skin, but someone touching her would feel her rough flesh. Otherwise, a creature must take an action to visually inspect the illusion and succeed on a DC 20 Intelligence (Investigation) check to discern that the hag is disguised.
Invisible Passage. The hag magically turns invisible until she attacks or casts a spell, or until her concentration ends (as if concentrating on a spell). While invisible, she leaves no physical evidence of her passage, so she can be tracked only by magic. Any equipment she wears or carries is invisible with her.
Legendary Resistance (3/Day). If Arlin fails a saving throw, she can choose to succeed instead.
Arlin can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. Arlin regains spent legendary actions at the start of her turn.
Turn Invisible. Arlin magically turns invisible for up to 2 turns. While invisible, she leaves no physical evidence of her passage, so she can only be tracked by magic. Any equipment she wears or carries in also invisible with her.
Rally, My Children! (Costs 2 Actions). Arlin rallies a nearby villager (Commoner), transforming them into a Cultist for the rest of the fight.
Awaken The Forest (Costs 3 Actions). Awaken the nearby trees, turning the trees in a 10 ft radius into awakened tree.
Description
((This is a custom boss monster personally tailored to my players and my campaign. Feel free to tailor to fit your needs.))
Lair and Lair Actions
On initiative count 20 (losing initiative ties), Arlin takes a lair action to cause one of the following effects; Arlin can’t use the same effect two rounds in a row:
- Arlin uses her illusory magic to mess with the mind of an enemy, imposing disadvantage on their attack rolls and saves made against her until the next round.
- Arlin consumes the heart of a nearby friendly target to regain 2d6 health.
Regional Effects
The region surrounding this town has been heavily tainted by dark magic over the centuries, which creatures one or more of the follow effects:
- Night time in the city and forest are darker than normal. Reduce vision by half.
- Vines will sometimes spring into action and grapple people. A successful DC10 Strength check will break them.