I have been playing and tweaking this with my DM for a bit now and it is really fun. It is based on the Realmspace infested star Hadar's various descriptions.
EDIT: I forgot to ask if anyone sees any weird interplay with this as a subclass. I am mostly in homebrew games with all sorts of tweaks, but we do try to stay as close to the RAW as we can.
Scion of Hadar
1 - Unquenchable Appetite Hadar is ruled by its hunger to survive by siphoning the energy from any source it can. Its favors are given to those who are able to supply the Dark Hunger with enough energy to sustain its dwindling flame. The warlock that is touched by the star’s power gains the ability to siphon the harm it places on others into itself.
When a target is damaged by a spell cast by the warlock, some of the target’s life force is transferred to the warlock as HP up to the warlock’s proficiency bonus. This transfer does not increase the spell damage and can only be applied once on the warlock’s turn.
6 - Erratic Movement Hadar is not a stationary star and tends to move in erratic ways through the distant realm it occupies.
When you cast a spell using a warlock spell slot, you can teleport to an unoccupied space you can see within 30 feet. Everything within 10' of the point you teleport from is pulled toward your new position.
10 - Insufferable Polyphagia Hadar’s hunger is all consuming and there are no other sources of discomfort that can erode the star’s drive to fulfill its desperation to satiate itself. The warlock can feel this drive across the eternal span of space and infuse their very soul inuring them against other desires. Hadar’s fight for survival is a constant battle against its own dying nature and it must use every grasp of life it consumes to fight against the degradation of its form. Hadar’s warlocks have been gifted the secrets of manipulating life-force to stave off ailments and toxins which could threaten to extinguish them.
You are immune to the Charmed and Frightened conditions. In addition, when health is transferred through The Unquenchable Appetite of Hadar feature, it can also end either the blinded, deafened, paralyzed, or poisoned conditions instead of transferring health to the warlock.
14 - Gravitational Tether Hadar’s need to draw the life-force of the living grants its warlock’s the ability to trap their prey for easier consumption. The warlock is granted the ability to tap into the great red star’s immense gravitational force to bind a target to a point in space.
Once per short rest you can magically tether one creature that you can see to the location it is currently at as a bonus action. The target’s movement speed is halved and it must make a strength ability check against your spell DC or suffer the Restrained condition. This tether last for 1 minute or until the creature takes an action to break free with a successful strength saving throw against your spell DC. Flying or swimming targets will appear stuck in the space they are occupying when tethered.
Alternate Spells: 1 Absorb Elements, False Life 2 Flaming Sphere, Kinetic Jaunt 3 Blink, Nondetection 4 Death Ward, Freedom of Movement 5 Immolation, Commune
I have been playing and tweaking this with my DM for a bit now and it is really fun. It is based on the Realmspace infested star Hadar's various descriptions.
EDIT: I forgot to ask if anyone sees any weird interplay with this as a subclass. I am mostly in homebrew games with all sorts of tweaks, but we do try to stay as close to the RAW as we can.
Scion of Hadar
1 - Unquenchable Appetite
Hadar is ruled by its hunger to survive by siphoning the energy from any source it can. Its favors are given to those who are able to supply the Dark Hunger with enough energy to sustain its dwindling flame. The warlock that is touched by the star’s power gains the ability to siphon the harm it places on others into itself.
When a target is damaged by a spell cast by the warlock, some of the target’s life force is transferred to the warlock as HP up to the warlock’s proficiency bonus. This transfer does not increase the spell damage and can only be applied once on the warlock’s turn.
6 - Erratic Movement
Hadar is not a stationary star and tends to move in erratic ways through the distant realm it occupies.
When you cast a spell using a warlock spell slot, you can teleport to an unoccupied space you can see within 30 feet. Everything within 10' of the point you teleport from is pulled toward your new position.
10 - Insufferable Polyphagia
Hadar’s hunger is all consuming and there are no other sources of discomfort that can erode the star’s drive to fulfill its desperation to satiate itself. The warlock can feel this drive across the eternal span of space and infuse their very soul inuring them against other desires. Hadar’s fight for survival is a constant battle against its own dying nature and it must use every grasp of life it consumes to fight against the degradation of its form. Hadar’s warlocks have been gifted the secrets of manipulating life-force to stave off ailments and toxins which could threaten to extinguish them.
You are immune to the Charmed and Frightened conditions. In addition, when health is transferred through The Unquenchable Appetite of Hadar feature, it can also end either the blinded, deafened, paralyzed, or poisoned conditions instead of transferring health to the warlock.
14 - Gravitational Tether
Hadar’s need to draw the life-force of the living grants its warlock’s the ability to trap their prey for easier consumption. The warlock is granted the ability to tap into the great red star’s immense gravitational force to bind a target to a point in space.
Once per short rest you can magically tether one creature that you can see to the location it is currently at as a bonus action. The target’s movement speed is halved and it must make a strength ability check against your spell DC or suffer the Restrained condition. This tether last for 1 minute or until the creature takes an action to break free with a successful strength saving throw against your spell DC. Flying or swimming targets will appear stuck in the space they are occupying when tethered.
Alternate Spells:
1 Absorb Elements, False Life
2 Flaming Sphere, Kinetic Jaunt
3 Blink, Nondetection
4 Death Ward, Freedom of Movement
5 Immolation, Commune
IMHO, Earthdawn is still the best fantasy realm, Shadowrun is the best Sci-Fi realm, and Dark Sun is the best D&D realm.