Actions

Multiattack. The gilman makes three Frostbow attacks.   Frostbow. The gilman magically shoots frost in a 60-foot line that is 5 feet wide. Each creature in that line must make a DC 17 Constitution saving throw. On a failure, a target takes 14 (3d8) cold damage and has its speed reduced by 10 ft. until the end of their next turn. On a success, a target takes half the cold damage, but does not have their speed reduced.   Hypnosis. The gilman projects a 30-foot cone of magical energy. Each creature in that area must make a DC 17 Wisdom saving throw. On a failed save, the creature is charmed by the gilman for 1 minute. While charmed in this way, the target tries to get as close to the gilman as possible, using its actions to Dash until it is within 5 feet of the gilman. A charmed target can repeat the saving throw at the end of each of its turns and whenever it takes damage, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature has advantage on saving throws against the gilman's Hypnosis for 24 hours.

Reactions

Spell Reflection. If the gilman makes a successful saving throw against a spell or a spell attack misses it, the gilman can choose another creature (including the spellcaster) it can see within 120 feet of it. The spell targets the chosen creature instead of the gilman. If the spell forced a saving throw, the chosen creature makes its own save. If the spell was an attack, the attack roll is rerolled against the chosen creature.

Legendary Actions

The gilman can take 1 legendary action, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The gilman regains spent legendary actions at the start of its turn.   Cast a Spell. The morkoth casts darkness, dispel magic, or misty step, using Intelligence as its spellcasting ability and without expending a spell slot.   Hypnotize. The morkoth uses its Hypnosis action, originating at a point within 120 feet of itself. It doesn't need to see the effect's point of origin.   Psychic Drain. One creature charmed by the gilman takes 10 (3d6) psychic damage, and the gilman regains hit points equal to the damage the creature takes.

Regional Effects

The water surrounding a gilman queen's lair is warped by the creature's presence, creating the following effects:   Alter Water. With a thought (no action required), the gilman can initiate a change in the water within its lair that takes effect 1 minute later. The water can be as breathable and clear as air, or it can be normal water (ranging in clarity from murky to clear).   Locate Creatures and Objects. The gilman is aware of any new arrival, whether an object or a creature, in its waters or in its sanctum. As an action, the gilman can locate any one creature or object on the island. Visitors to the island feel as though they are being watched, even when they aren't.   Lost Possessions. Each time a creature that has been within the waters for less than a year finishes a short or long rest, it must make a DC 10 Intelligence saving throw. On a failure, the creature has misplaced one possession (chosen by the player, if the creature is that player's character). The possession remains nearby but concealed for a short time, so it can be recovered with a successful DC 15 Wisdom (Perception) check. An object that is misplaced but not recovered ends up in the gilman's lair 1 hour later. If the creature later goes to the gilman's lair, its lost possessions stand out in its perception and are easily recovered.   Supernatural Lure. Entrances to the gilman's lair have an enchantment that the gilman can activate or suppress at any time while it's in its lair and not incapacitated. Any creature within 30 feet of such an entrance and able to see it must make a DC 15 Wisdom saving throw. On a failed save, the creature feels an intense urge to use its movement on each of its turns to enter the lair and to move toward the morkoth's location (the target doesn't realize it's heading toward a creature). The target moves toward the gilman by the most direct route. As soon as it can see the gilman, the target can repeat the saving throw, ending the effect on itself on a success. It can also repeat the saving throw at the end of each of its turns and every time it takes damage.   If the gilman dies, these regional effects end immediately.