Will-o 'Wisp

Tiny undead, chaotic evil

Armor Class 19

Hit Points 22 9d4

Speed Hover: 50ft

STR

1 -5

DEX

28 +9

CON

10 0

INT

13 +1

WIS

14 +2

CHA

11 0

Damage Resistances Acid, Cold, Fire, Necrotic, Thunder; Bludgeoning, Piercing, and Slashing from nonmagical attacks

Damage Immunities Lightning, Poison

Condition Immunities Exhaustion, Grappled, Paralyzed, Poisoned, Prone, Restrained, Unconscious

Senses darkvision 120 ft., passive Perception 12

Languages the languages it knew in life

Challenge 2 (450 XP)

Consume Life: As a Bonus Action, the will-o’-wisp can target one creature it can see within 5 feet of it that has 0 hit points and is still alive. The target must succeed on a DC 10 Constitution saving throw against this magic or die. If the target dies, the will-o’-wisp regains 10 3d6 hit points.
Ephemeral: The will-o’-wisp can’t wear or carry anything.
Incorporeal Movement: The will-o’-wisp can move through other creatures and Objects as if they were difficult terrain. It takes 5 1d10 force damage if it ends its turn inside an object.
Variable Illumination: The will-o’-wisp sheds bright light in a 5- to 20-foot radius and dim light for an additional number of feet equal to the chosen radius. The will-o’-wisp can alter the radius as a Bonus Action.

Actions

Shock: Melee Spell Attack: +4 to hit, reach 5 ft., one creature. Hit: 9 2d8 lightning damage.
Invisibility: The will-o’-wisp and its light magically become Invisible until it attacks or uses its Consume Life, or until its Concentration ends (as if concentrating on a spell).