fascinating idea having revenge justice juxtaposition, the only thing I could suggest for it to be different from other persona games is that mayhaps as Persona series shows that are individuals aware of it mayhaps the protagonists being inspired by the phantom theives purposefully seek out such power and possibly unlike the natural gravitation of most persona protagonists and their group they actively recruit others rather than have them accidentally join, make it so instead of the protagonist accidentally finding their allies that they purposefully seek them out, another is having perhaps both protagonists be wild cards or mayhaps originally being normal persona users but after being betrayed they are experimented on and possibly through nyarlothoteps intervention become wild cards
Precarity version
Mayhaps the protagonist and party have to save a person from a doppelganger of sorts or idealized self much like in
The persona story 'in the eye of the beholder', if they don't they could die from a form of 'karoshi' ie death by overwork and in this case death by overclocking the physical body beyond its limits funfact I accidentally discovered the concept on complete accident
Horror theme idea
Mayhaps the protagonist can be a shadow like teddy specifically the shadow Doppelganger as a sort of inverted version of a wild card instead of multiple persona he instead can assume one by linking with someone and awakening their inner potential, admittedly I've been toying with this concept for bit in my own persona fic idea
Here's sanitized version of the idea not going to spoil anything from my project, doppelgangers primary gimmick is basically becoming a persons shadow to stabilize their existence and identity without 'devolving' into a lesser shadow like akira can recruit but can not stay with any weilder for too long or risk losing their identity by basically becoming them a recurring phrase with dopoelganger being 'Thou art I, I become Thou'
Doppelganger
Appearance like a vaguely human entity, long and wild hair enshrouding its androgynous form, yellow eyes, its expression though corpse like is gently smiling, body is rigid and skeletal, they wear black clothes that are black and tattered, wears an overly large hat that puts the face in shadow leaving the eyes as the only describable features
Intro phrase: "thou art I, I become thou, from the outer reaches of your knowledge I come, a faithful companion till your hour of death or you need me no more, Doppelganger at your service."
Social link arcana the Beggar arcana whose personas are urban legends like slenderman, bloody mary, Ghost train, kuchisake onna etc, fairytale characters like the frog prince, blue fairy, puss in boots, monstro, etc, fictional characters and creatures from popular stories such as say the jabberwocky, cheshire cat, mindflayer, mimics, various characters embodying job/classes from videogames, western dragons etc
Death arcana
No set skills or abilities nor affinities except, water, ice, debuffs, an accuracy buff, and instant death chance, weak to fire, can temporarily become other personas or assume the position of one till a person awakens their persona, over the story absorbs shards of power/potential from both the protagonist, party and enemies, can create, weild or temporarily become 'variant' personas of the party like say the picaro personas from P5 prefers fire resistant or fire proof personas though, hates the fact that due to how many female wielders they've been attached to it's made them girly…. And worried that they will fade away to be become a mindless doppelganger Rather than be Doppelganger, to devolve into a 2 dimensional sub sentient thing and the reason why they do what they do, to remain unique and differentiated rather than become some husk of what they were by taking power from villains and use it to solidify their own identity, tries to remain aloof from his hosts but starts failing after spending to much time with them,
Possible persona
Atropos
Unique ability Severance: to separate, a shadow from its person, an area from its surroundings, compartmentalize cognitve areas and memories, etc
Note persona requires special circumstances to come into being, outside intervention from greater cognitive being?
Ps link to persona fic I mentioned
Edit revenge persona idea, The Green knight from arthurian legend could make for an interesting persona due its story
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