The alienists deal with powers and entities from terrifyingly remote reaches of space and time. Best described with adjectives like eldritch, unfathomable, or unspeakable, the entities from the most distant realms are channeled into the Material Plane, manifesting as bane to all mortal sentience and blessings to those who are willing to risk a fragment of sanity in return of immense power it grants.

In most societies, alienists are treated just like the entities they deal with - blasphemous, dangerous, insane, and most of all, different. Most alienists take such hostility and apathy as ignorance of mortal beings, not knowing how insignificant they are compared to the world theyknow. Some alienists suffer from their inner dilemma, and very few even seek to protect their beloved world and realms against the alien terror with the very same power they "stole" from the farthest corner of the world.

The Alienist subclass is inspired by and based on the Alienist prestige class from the 3.5rd edition supplement Complete Arcane

Aberrant Inclination

When you choose this tradition at 2nd level, whenever you make a Charisma check when interacting with aberrations, your proficiency bonus is doubled if it applies to the check.

Additionally, you can speak Deep Speech. Although it is very uncommon to see Deep Speech in written forms, you can read and write Deep Speech written in any scripts you can read or write.

Pseudonatural Companion

Blessings from Insanity

Starting at 6th level, when you make a Intelligence, Wisdom or Charisma checks or saving throw, you can choose to gain advantage on the die roll. Each time you use this feature before you finish a long rest, you gain a culminative -1 penalty to all Intelligence, Wisdom or Charisma checks and saving throws. When you finish a long rest, the penalty resets to 0.

Unfathomable Mentality

At 10th level, you and your pseudonatural companion develop mental oddities. Your companion has immunity against psychic damage, and it is immune to being charmed or frightened.

Additionally, you have advantage on saving throws against being charmed or frightened.

Timeless Body

When you reach 14th level, your association with alien entities greatly renders your physiological activities different from what it should be. You suffer none of the frailty of old age, you cannot be aged magically, and you no longer need food or water to survive. However, you can still die of old age.

Additionally, you can use your action to expend one spell slot to channel your magical power to your pseudonatural companion, if it is within 100 feet of you. Your pseudonatural companion gains 1d6 hit points per level of spell slots you expended. If you expend a spell slot of 6th level or higher, it also gains the benefit of the greater restoration spell, as if you had cast it on your companion.