This is a homebrew rule created by David Jackman

Sources used for this Rule creation

• Dungeon Master’s Guide
• Player’s Handbook
• Xanather’s Guide to Everything
• Sword Coast Adventurer’s Guide
• Monster Manual
• Tal’Dorei Campaign Setting

Side note

This rule can be adjusted for divine possession (I may write a dedicated version at a later date)

Pre-requisites for this character feature

In order for this feature to be used for a character (specifically Player Character) one of the following things must be true:

1. The character must be a Warlock and have made a pact with a demon and the demon has taken up residence in the players body
2. The character must be a Warlock and have made a pact with a Devil and the Devil has taken up residence in the characters body

OR if the character is not a Warlock:

• The demonic possession must make sense with their back story and would likely result in the character having one of the following backgrounds (PHB pg127-141, CoS pg209-210 and T’DCS pg105-109):
  • Acolyte (PHB pg127)
  • Haunted One (CoS pg209)
  • Recovered Cultists (T’DCS pg105)

(These backgrounds can be used for a Warlock character class background as well)

• It is possible for the player to create a Cleric and run the possession feature for their character depending on the domain/background combination chosen (discussion with the DM to pick appropriate ones)

Rules for using this feature

A player possessed by a devil or demon must succeed on a daily CHA saving throw with a starting DC of 10. Upon a failure the devil of or demon controls the character until the end of the next long rest. After a failed save the DC for the save increases by 1 each time stopping once the save has a DC of 20. Saving throws should also be made in areas of a strong evil presence or a place that sparks an emotional memory about the place the initial possession took place at the discretion of the DM.

Changes that occur under possession

If the player fails the save and the entity within has taken control the following stands:

1. The character’s alignment becomes Chaotic Evil
2. The character has advantage on Deception rolls
3. The character has advantage on Persuasion rolls
4. The character has advantage on Intimidation rolls
5. The character has disadvantage on Animal Handling rolls
6. The character has disadvantage on Medicine Rolls
7. The character has disadvantage on Perception Rolls
8. The character has disadvantage on Nature Rolls
9. The character becomes resistant to necrotic damage
10. The character becomes immune to being charmed
11. The character becomes vulnerable to radiant damage
12. The character becomes vulnerable to force damage
13. The character becomes vulnerable to lightening damage

Second Wind

If a Character who is possessed is reduced to zero hit points, they regain hit points equal to 1d6. If the character was under the entities control when this happened, then the players character resumes control of the body. If the entity is supressed at the time of reaching zero hit points, then the entity will take control of the unconscious character until the end of the next long rest. This can only occur once per long rest.

Under the demon’s control

Under the demon’s control the aims and goals of the entity are what the player should work towards, starting a new cult, world domination or unleashing a world ending evil on the world.

Unarmed attacks have a +3 necrotic damage to rolls.

Release Control

Once per long rest the controlling entity (either Demon or Character) as a bonus action (in combat) can release the control of the body to the suppressed entity at that time. Which ever entity then takes control has control until the end of the next long rest, at which point control will be determined by a CHA saving throw