Displacer Beast CR: 3

Large monstrosity beast,

Armor Class: 13 (natural armor)

Hit Points: 85 ( 10d10+30 )

Speed: 40 ft

STR

18 +4

DEX

15 +2

CON

16 +3

INT

6 -2

WIS

12 +1

CHA

8 -1

Senses: darkvision 60 ft.

Challenge Rating: 3

Avoidance The Beast only takes half dmg from effects that opt for half damage, and no damage on a successful save.
Displacement The Beast projects a magical illusion that makes it appear to be standing near its actual location, causing attack rolls against it to have Disadvantage. If it is hit by an attack, the trait is disrupted until the end of its next turn. This trait is also disrupted while the Beast is incapacitated or has a speed of 0.

Actions

Multiattack The Beast makes two attacks with its Tentacles.
Tentacle Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 1d6+4 bludgeoning damage plus 1d6 piercing damage.