Fell Sentry

You have become a void of emotions, due to your time spent in the Shadowfell, coming across a Shadow, interacting with a monument/item from the Shadowfell, or some other unknown event. However you acquired your fell magic, you are now a Fell Sentry, a ranger who represents both the mortal and the shadow realms. As you traverse the multiverse, your focused mind and your numbed heart allows you to focus and succeed on tasks and missions even in moments of extreme peril, and your martial prowess leaves your enemies struggling to move. The shadows are cold, and your enemies will know their embrace.

Eerie Swiftness

3rd-level Fell Sentry feature

You have become accustomed to hunting and traversing in the vast emptiness of the Shadowfell. When you take the Attack action, before or after any of your attacks you can move up to half of your speed. You can only do this once per turn. Additionally, creatures attacked by you have their speed reduced by 10 ft. and attacks of opportunity made against you while moving have disadvantage.

The movement increases to your full speed and the speed reduction is in increased to 15 ft. when you reach 11th level in this class.

Fell Sentry Magic

3rd-level Fell Sentry feature

You learn an additional spell when you reach certain levels in this class, as shown in the Fell Sentry Spells table. Each spell counts as a ranger spell for you, but it doesn’t count against the number of ranger spells you know.

Fell Sentry Spells

Ranger Level	Spells
3rd	protection from evil and good
5th	darkness
9th	summon shadowspawn
13th	greater invisibility
17th	far step

Your body has also been influenced by the penumbral forces of the Shadowfell. Choose your somber influence from the Shadowfell Influence table or determine it randomly.

Shadowfell Influence

Serene Grit

3rd-level Fell Sentry feature

Your experience in the empty hollows of the Shadowfell has given your mind an uncanny focus. As a result, whenever you make a Intelligence check, you gain a bonus to the check equal to your Wisdom modifier (minimum of +1).

In addition, you gain proficiency in one of the following skills of your choice: Arcana, Investigation, or Nature.

(Note: Couldn't make a specific list for the skills)

Etiolate Emotions

7th-level Fell Sentry feature

The vast emptiness of the Shadowfell has hardened your mind, and strengthened your will . You have resistance to necrotic damage.

In addition, whenever a creature you can see casts a transmutation, necromancy, or enchantment spell, you can use your reaction to force the caster to make a saving throw against your Spell DC. if they fail, the spell goes off as if you cast it on them. You can do this a number of times equal to your proficiency bonus per long rest.

Shadow's Aid

11th-level Fell Sentry feature

You can summon a creature of the Shadowfell to aid you and your allies. As a bonus action, you can summon a shadowy figure (You determine what the shadowy figure looks like) and command them to follow you or one of your allies for 1 minute. The shadowy figure provides the creature it is following a bonus to their attack rolls and saving throws equal to half your proficiency modifier (rounded down), and resistance to one damage type of your choice. The shadowy figure is completely incorporeal, and can not be harmed or targeted by any spells.

You can use this feature a number of times equal to your Wisdom modifier every long rest.

Sound Mind

15th-level Fell Sentry feature

Your time spent in your own mind has given you the chance to organize all of your thoughts. You can use your reaction to reroll any Intelligence, Wisdom, or Charisma Save or check. 

You can use this feature a number of times equal to your Wisdom Modifier per Long Rest. You expend a use only on a success.