Nyctophobia

The archetypal Nyctophobia combines the martial mastery common to all fighters with the constant fears of the Dark. Nyctophobia Fighters uses the mystery of darkness to terrify their foes while covering their attacks. They focus their power on the shadows, making them into their offense and defence. Surrounded by the echoes of their own blade cutting though the unsuspecting opponents, they cloak the battlefield in a cycling swarm of shadows and strikes.

Mantle of Darkness

Starting at 3rd level, you can use a bonus action to grow the shadows and rap around your very being, the area within 10ft of you is classed as dim light. This feature lasts until you end it as a bonus action.

You have also learnt to manipulate the shadows of others, using them to your advantage. If your Mantle of Darkness overlaps with another source of dim light, the overlapping spaces act as darkness.

• Creature Shadows, are classified as dim light for you. 
• Creature Shadow Sizes, are equal to the Creature size, as specified in Size Categories.
• Creature Shadow Locations, are to one side of the given creature, to the DM's discursion. 

Fearful Strength

Starting at 3rd level, your connections to night provides you gifts of Fear.

Fear DC equals (8 + Constitution modifier + proficiency modifier) 

One per turn, you can imbue a weapon with Fear. When you take attack action you can choose to attack with disadvantage. If you do, regardless of whether or not you hit, the target must make a Wisdom save against you Fear DC or the creature become frightened of you until the start of your next turn.You can use this feature a number of times equal to your Constitution modifier (minimum of 1) regaining expended uses on a short or long rest

In addition, your eyes adapt to the shadows, you gain 60ft of Darkvision, or an extra 30ft if your race grants darkvision.

Darkness' Missionary

At 7th level, you bend the shadows to your will, you gain resistance to necrotic damage and you can cast the Darkness spell once per short or long rest, without needing components or a spell slot.

In addition, the darkness guilds you moves, you gain Blindsight of 20ft while you are in darkness, even those considered magical in nature.

Enhanced Terror

At 10th level, you manipulation of the dark has helped you strike fear into the hearts of your foes. When a creature has the frightened condition within your Mantle of Darkness their movement reduces to 0.

In addition, your Mantle of Darkness increases to a 20ft area around you.

One with Shadows

At 15th level, you gain the ability to meld with the shadows. As a Bonus action, you can Merge your physical form with an space of darkness. Your Mantle of Darkness can still be seen while merged unless it is fully overlapping with an area of darkness.

While Merged : 

• You are classified as invisible.
• You can use your Reaction, to teleport up to 30ft to another space of darkness.
• You can use your Action, to pull a creature within your Mantle of Darkness into the shadows. The target creature must make a wisdom save against your Fear DC or take 3d10 psychic damage and are grappled. The target can end the grapple by either repeating the save at the end of their turn, or if they leave the Mantel of Darkness. When grappling creatures this way your movement isn't reduced to 0.
• You can use your Bonus action, to prematurely end being Merged, causing a number of creatures equal to your proficiency bonus within your Mantle of Darkness to make a wisdom save against your Fear DC or become frightened of you until the end of your next turn.

This feature ends after 1 minute, you can use this feature a number of times equal to half your proficiency bonus (rounded down) per long rest.

Shadow Scythe

At 18th level, you can command the darkness to carve its form into a large, black scythe with a blade resembling a crescent moon. As a Bonus Action, you can consume your Mantle of Darkness to Create the Shadow Scythe.

Weapon States:

• Classified as magical for purpose of overcoming resistance
• Gain a +3 Bonus to attack and damage rolls
• Deals (1d12 + 2d6) necrotic damage on a hit
• Weapon properties: Two-handed, Finesse
• Night's Nightmare. In addition, as an action, you can consume your enemies with fear, creatures of you choice within a 20ft of you must make a wisdom save against you Fear DC or become frightened of you and blinded for 1 minute. The target can end this effect by repeating the save at the end of their turn. Once used, this property can not be used again until the next time this feature is used.

This feature lasts for either 1 minute or untill you use a Bouns action to end it. Once used, you Mantle of Shadows reappears and this feature can not be used again until the next dusk