Necroscope

The term necroscope describes someone who can communicate with the dead (coined Deadspeak). Unlike necromancers, who extract the knowledge they seek by brutal eviscerations of corpses, a necroscope can communicate with them as equals: peacefully and without any physical interference. The abilities of a Necroscope are defined as a type of ESP.

Deadspeak/Mobius Mobility

Deadspeak:

Starting at 1st level, you have Deadspeak with a range of one mile. When you reach 3rd level in this class, your Deadspeak sense increases in power and you can reach out to any dead mind wherever you are as long as you have made initial contact by visiting their place of rest. The dead mind must still be on the same plane of existence in order to do this unless they are tapped into the Mobius Continuum. This ability also awakens telepathy within the Necroscope.

Mobius Mobility: 

Starting at 1st level, using the mathematical calculations taught to the first of them by August Ferdinand Mobius, a Necroscope can conjure a door to the Mobius Continuum. By traveling through this door, they can instantly teleport to any place in the plane of existence they currently occupy. They can also travel through time but can only appear in the past and future as an astral projection of themselves. While in this form, they can speak to people, but cannot interact physically in any way. Moving into and out of the Mobius Continuum is a standard move action.

Mind Blanket

As a bonus action, a Necroscope can cover their mind in a psychic blanket, effectively shielding their thoughts from others. This blanket prevents the Necroscope from being contacted or influenced telepathically but also blocks their telepathic abilities. This blanket also makes them immune to scrying.

Locator

The Necroscope's telepathic abilities enhance and evolve, developing scrying capabilities. By connecting with another mind, a Necroscope can locate them as if using a scrying spell and appear near them through their Mobius Mobility ability.  This also works if the mind is on another plane of existence.

A Necroscope must focus on a mind for one minute if they are on the same plane and ten minutes if they are on a different plane.

Necroscopic Resurrection

The Necroscope can call for assistance from all the dead within a one-mile radius. They choose whether or not to rise physically to their aid. Through a spoken incantation, the Necroscope can bring the dead back to full animation. This incantation takes a ritual casting but once it is completed, the Necrocope can move freely without having to maintain concentration.

The Dungeon Master gets to establish what kind and how many of the Teeming Dead respond to the Necroscope's call. The DM and the player can decide who will control the Dead who rise and if they will function as a horde, with specific stats, or both.