You have made a pact with the spirit of a deity that has been dead so long no one remembers her name. Her echo, however, remains with a certain strength to it, and through this echo she gives you power over liminal spaces and that which passes between.
Expanded Spell List
Spell Level — Spells
1st — Silent image, sleep
2nd — See invisibility, spiritual weapon
3rd — Blink, gaseous form
4th — Greater invisibility, phantasmal killer
5th — Cloudkill, cone of cold
You are versed in things ethereal. When you take this patron at 1st level you become proficient with the Religion skill. You have advantage on Charisma-based skill checks when dealing with ghosts that can understand you.
At 1st level you are bequeathed an artifact called a Medium’s Reliquary as a token from the Forgotten Goddess. This can look like any item through which you can see a glow from the inside: a gem in an elegant necklace, a wrought iron lantern or an orb affixed to the end of a staff are all perfectly viable options.
The Medium’s Reliquary holds souls. Whenever a creature you can see dies within 30 feet you can use your reaction to capture its soul before it can pass on. This ability has no effect on undead or constructs.
Your Medium’s Reliquary can contain a number of souls equal to your Charisma modifier (minimum of 1). The souls inside your Medium’s Reliquary are safe, and unaware of what is happening around them within or outside.
As an action you can release a soul from your Medium’s Reliquary. The soul manifests as a creature based on the Medium’s Reliquary Table. The creature is under your control for 5 minutes and you can use your bonus action to issue a command. At the end of the duration the soul dissipates and passes on. You cannot reclaim the soul a second time.
You may also use a bonus action to consume one of the souls from your Medium’s Reliquary, healing a number of hit points equal to your Charisma modifier + your warlock level.
Medium’s Reliquary Table
Warlock Level — Creature
1st — Shadow
6th — Specter
10th — Will-o’-wisp
14th — Banshee
17th — Wraith
At 6th level, you harness the power of the Forgotten Goddess’ miasma and are able to put it to work for you. As an action, you emit a misty miasma of chaos in a 15 foot radius. Creatures you choose that begin their turn within the miasma must succeed on a Wisdom saving throw against your spell save DC or become swayed by your chaotic emanations. Whenever an affected creature takes the attack action it must choose the target at random from among the creatures it can see within range of the attack.
From the Silent Shore
At 10th level, you may take a soul from your Medium’s Reliquary and place it into another body. As long as that body is capable of life, the soul will take root in it, and for all intents and purposes be alive again. The creature has the same stats they used to, but with the racial modifiers of their new body rather than their old one.
Of Flesh and Soul and Malice
At 10th level, you gain the ability to take a ghost form. While in ghost form, you may use a bonus action to enter the ethereal plane from the material and vice versa. When you are on the ethereal plane, you can see 60 feet into the material plane and vice versa. You can move through other creatures and objects as if they were difficult terrain. You take 1d10 force damage if you end your turn inside an object. You may maintain this for a number of rounds equal to your Charisma modifier (minimum of 1). If your ghost form ends with you on the ethereal plane, you are shunted back onto the material. In ghost form, you do not have to breathe, and you have resistance to bludgeoning, piercing and slashing damage from nonmagical weapons.
Swarm of Souls
Starting at 14th level, you may surround yourself with a swarm of souls from your Medium’s Reliquary for one round, as well as pulling any from the surrounding area. Any ghosts within 100 feet of you are drawn to your side in a phantasmal vortex. Creatures you choose that you can see must make a Wisdom saving throw or take 10d10 necrotic damage. You may then regain that many hit points. If the save fails by 5 or more the target also ages 1 year per spirit in your vortex. You may then reverse your own age by that many years if you choose as you siphon the life from your targets. You may not use this ability again until you have completed a long rest.
Forgotten Oasis includes this new Otherworldly Patron — The Forgotten Goddess, who grants power over liminal spaces and that which passes between. There’s also the NPC Digit, a humanoid construct build for calculating figures and probabilities, 3 new magic items, 3 new creatures and an adventure! Check it out here.
[NERDITOR’S NOTE: This post and the Forgotten Oasis product itself were revised and updated May 12, 2020 at 10:25 p.m. to reflect a significant change to the Forgotten Goddess warlock’s Medium’s Reliquary feature. If you purchased this product from Nerdarchy the Store you can login and download the revised version. Those who backed Out of the Box: Encounters for 5th Edition at the Ethereal Summoner and Demigod level will find the updated version there as well.]