Sources
CR
Type
Size
Alignment
Movement

Eldritch Eddy

Large Construct, Chaotic Neutral

Armor Class 11
Hit Points 144 (17d10 + 51)
Speed 10 ft., fly 40 ft. (hover)
STR
10
+0
DEX
12
+1
CON
16
+3
INT
12
+1
WIS
9
-1
CHA
17
+3
Saving Throws DEX +4, INT +4, CHA +6
Damage Resistances force
Damage Immunities fire, lightning
Condition Immunities Charmed, Exhaustion, Frightened, Paralyzed, Petrified, Poisoned
Senses Blindsight 60 ft., passive Perception 9
Languages understands Common plus one other language but can't speak
Challenge 6 (2,300 XP)

Traits

Magic Resistance. The eddy has Advantage on saving throws against spells and other magical effects.

Actions

Multiattack. The eddy makes two attacks, using Searing Swipe or Arcane Bolt in any combination.

Searing Swipe. Melee Attack Roll: +6, reach 10 ft. Hit:13 (3d6 + 3) Fire or Lightning damage (eddy's choice).

Arcane Bolt. Ranged Attack Roll: +6, range 120 ft. Hit:14 (2d10 + 3) Force damage.

Reactions

Eldritch Overload. Trigger: The eddy takes damage. Response—Strength Saving Throw: DC 14, each creature of the eddy's choice in a 5-foot Emanation originating from the eddy. Failure: 7 (2d6) Force damage, and the target has the Prone condition.

Lore

When magical energy becomes dangerously unstable, it sometimes animates into an eldritch eddy: an uncontrolled whirlwind of Evocation magic that crackles with fire and lightning. Eldritch eddies typically arise where magic use is heavy and irresponsible, such as near a fanatical mage's sanctum, a workshop that churns out magic items, or a library where undertrained scribes work with Spell Scrolls. Eldritch eddies are common in ancient Netheril near the homes and workplaces of famous mages.