Ambusher. The hulk has advantage on attack rolls against any creature he has surprised.
Anathematic Secrecy. The hulk can't be targeted by any divination magic or perceived through magical scrying sensors.
Avoidance. If the hulk is subjected to an effect that allows him to make a saving throw to only take half damage, he instead takes no damage if he succeeds on the saving throw, and only half damage if he fails.
Innate Spellcasting. The hulk's innate spellcasting ability is Constitution (spell save DC 15). He can innately cast the following spells, requiring no components:
At will: enemies abound, pass without trace
3/day each: dispel magic, fear, invisibility
2/day each: phantasmal force, phantasmal killer
1/day each: control weather, feeblemind
Magic Resistance. The hulk has advantage on saving throws against spells and other magical effects.
Magic Weapons. The hulk's weapon attacks are magical.
Sneak Attack (1/Turn). The hulk deals an extra 7 (2d6) psychic damage when he hits a target with a weapon attack and has advantage on the attack roll, or when the target is within 5 feet of an ally of the hulk that isn't incapacitated and the hulk doesn't have disadvantage on the attack roll.
Unyielding Essence. The hulk is immune to any spell or effect that would alter his form, as well as those that would read his thoughts, determine if he is lying, or magically influence his thoughts or behavior.
Multiattack. The hulk uses his Hypnotic Gaze if it is available, then makes two poisoned spike attacks.
Poisoned Spike. Melee or Ranged Weapon Attack: +8 to hit, reach 5 ft. or range 100/320 ft., one target. Hit: 9 (1d8 + 5) piercing damage plus 10 (3d6) poison damage.
Hypnotic Gaze (Recharge 6). The hulk attempts to hypnotize up to two creatures he can see. Each target must succeed on a DC 15 Wisdom saving throw or be stunned until the start of the hulk's next turn. Each time a target takes damage, it can repeat the saving throw, ending the effect on itself on a success.