This is admittedly an idea I've been letting rattle around in my head for a while. It's not fully thought out, but I have thought about how it work for a while.
Basic Idea
My idea is to combine the concepts of blood born with cyberpunk ethics. With some inspiration from Overkill. You wake up in a cyber city overwhelmed by a medical power source called "Spark" by the company who discovered it, Steven Cyberware. Your very existence is considered an affront to company policy and an unwanted factor the corporation doesn't want to understand or use (Think of it similar to Far Zenith from Zero Dawn). So they send a clean-up crew to destroy the isolated island lab you're on. You likely die (And rise out of a light blue sea of geometry onto an island with a lighthouse observatory known as Shoreline) or run away (you'll be invited to the Shorline, a cyberspace isolated and hidden in the network where people like you may hide). In Shoreline, a chip and jovial person known as "S.k.I.E." will meet you. A friendly and acts as a shrine made of the game. You'll also find other NPCs here who you can meet in the real world as well. Other NPCs who've come here for one reason or another.
The shoreline is a hub world, With it largely being where docs amongst the small coastline with small huts and shops. on the boats With the centerpiece of S.k.I.E.'s Lighthouse and observatory. Where she can use concentrated Spark and data you get from enemies to upgrade your stats. Further on in the game, This place will slowly change. The Sea will start to show faces and limbs of glitching complexions of grey, boats trying to prepare to depart. At the end game, the sea will be red as the sky sparks and sputters. Boats in the distance or at the docks wrecked or sinking. The place is now marked and surrounded by beings wanting to feed. S.k.I.E. Now showing some worry, as she tries to hide their fear behind a smile. Trying not to think about what could happen to her. (Here, you could possibly catch her crying, to which she'll stop and say she's fine if asked. If you can listen to her out of sight though, you could hear her talk to herself in private. trying to focus on anything but the fear of oblivion she might be subjected to, or worse, she stays conscious as she's torn apart by eldrich things. You may even see her mind degenerating as bits of it go away. eaten by uncaring gods. Her anger and sadness at not being able to remember the faces of people they care for. She's terrified and trying to hide it so you may complete her mission of helping you, the thing she was made to do. But she also doesn't want to die).
The Save system is made up of transition nodes. Massive cell towers that many have plugged into so they can escape the nightmare inflicted upon them by corporations and spark. With Ancient beings coming from another realm to feast upon spark. Some plugging in and never coming back. You need to activate these nodes to fully create systems online (Kinda like how you need to unlock towers to fast travel in breath of the wilds). Around the area, there are fabricator Nodes. Acting as the primary save points. Where some will actively be around these Nodes to top up on spark. A vital resource to survive outside the Corporations and the City Council. With Many enemies are robots or cybernetically enhanced guards and creatures from one of those two factions, or gangs. Later on, spark creatures will emerge. Often around unoccupied Spark nodes.
The goal of the game is to either destroy all five Spark capacitors, or your original mission of getting to the top of Marigold Tower, a luxury tower for the high society in the past, now a fortified fortress where the companies keep the portal open and keep harvesting Spark from the grey world. The High society doing nothing but maintaining their lifestyle and power. To them, they'd rather rule the world, even if it's nothing but ashes than ever lose power. They'll die eventually, so what about the consequences. They also want you and others like you gone. To them, you're spit in their face by someone who defied them, and an unknown variable. Some smarter ones will try and use you for their own ends (connected to one of the endings). But in the end, they will prioritize their power and pride over others.
Lastly (For now), there would be "The Spark Beings". Those Eldrich gods mentioned earlier. These are otherworldly beings who consume Spark. Alongside having some intelligence and motives you don't get to fully know. They do want to eat though. Which can collapse the entirety of society and everyone who has spark even remotely near them (Everyone who still lives). This is actually something your creator is interested in. I should explain your Creator.
Your creator and by extension creator of the shoreline is named Alisa Burg and her persona is "Hustin Hills". A former tech billionaire who helped build up the corporate society and its reliance on spark. However, she was kicked out of high society and forced out of the oppressive corporation she helped found. Alongside being forbidden to continue her research which was deemed company property. However, as soon as the eldrich beings where dicovered, she started drafting up plans. Eventually becoming one of the most wanted people in the city as a result of body snatching from the morg, illeagal experimentation with trademarked technology, and other such crimes. One of which was you. (With your purpose not being to save the world, but to instead assign yourself or your creature into one of these eldrich gods).
Combat
Combat focuses on dodging and striking. With All enemies holding the resource known as "Spark". A resource that acts as your health. You can even recover health by bathing in the Spark that spews out of enemies. The most spark is gotten either by striking an enemy during an attack where you can get a slight healing, or striking a death blow that gives you some Hp and refills a charge of your Spark Charg (Estice flask equivalent). You can also recharge weapon abilities with these. With quick weapon changes and modifications also being key.
Cybernetics act as special talismans or charms that can help certain things happen. With Chips acting like spells, your character can be used for spells. Extra spark is restored by attacking an enemy right after they make an attack. landing a death blow, or by getting a recharge.
it'll largely be melee-based, with range weapons tacking sparks. With most everything ranged needing it to power up, or use as ammunition.
