Coeurl (Epic)

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

Displacement. The coeurl 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, this trait is disrupted until the end of its next turn. This trait is also disrupted while the displacer beast is incapacitated or has a speed of 0.

Magic Weapons. The coeurl's attacks are considered magical. 

Mobile. A creature attacked by a coeurl (whether successfully hit or not) cannot use an opportunity attack against that coeurl during the same round the creature was attacked. 

Multiattack. The displacer beast makes four attacks with its tentacles.

Tentacle. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 14 (2d6 + 7) bludgeoning damage plus 14 (3d8) lightning damage. A creature hit this way must make a Constitution Saving Throw (DC 19) and is Slowed upon failure until the start of the Coeurl’s next turn. A Slowed creature hit this way must make a Constitution Saving Throw (DC 20) and is Stunned upon failure until the end of the Coeurl’s next turn. A Stunned creature hit this way must make a Constitution Saving Throw (DC 21) and is Petrified upon failure.