Silver Symbiosis Windows game

A destructible/manipulate-able environment which can be affected by the Fusion skills (Examples; changing solid ground to swamp or quicksand, causing land-/rock-slides, etc...)
Massive world with many terrain types
Hostile environments where the world itself can kill the unprepared through extreme heat (magma caves and deserts), extreme cold (high altitude and/or far northern/southern latitudes), drowning, or starvation.
Ability to ATTEMPT to negotiate with most hostile creatures, many of whom may respond favorably, thereby granting new Fusion abilities(certain bosses) or trade for rare items("normal" enemies) while others will take advantage to do massive damage or even (in the case of bosses) 1-hit kills
Real-time combat which pauses while in the skill or item menus allowing the player to take their time while browsing through them
Ability to acquire recipes, gather ingredients, and prepare potions and/or food
Trade with NPCs
A multitude of creatures to encounter. Many hostile, but not all

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It takes place on Earth in the future.
The laws of reality have changed
Fossil fuels are useless
Global economies crashed when oil became useless/worthless
They have had about 20 years or so to recover but the balance of power has shifted irreparably in the mean time
Chemical propellants and explosives no longer function
Military superpowers (USA, China, etc..) have lost their military superiority when their weapons and vehicles stopped functioning
In poor areas technology has regressed back to the level it was at in the 1700’s and transportation is via pack animals
In rich areas technology has progressed forward to the point that laser rifles are commonplace and all transportation is via electric vehicles, primarily hovercraft
Main characters are twin brother and sister in their mid-teens
Only one is playable, which that is depends on the gender selected at the start of the game.
Eye and hair color(after the fusion with the symbiote) of the main(player) character is metallic silver. Before that both hair and eye color are mahogany brown.
Rifts have opened all over the globe allowing creatures from other realities to come into our world
Some of these creatures want to go home but cannot (ex. Dragon)
Others want to establish interdimensional trade routes (ex. Gnolls)
Some want to raid our world for resources not available in theirs (ex. Rock-Goblins and wood)
Some want to destroy for the sake of destruction (ex. Wraith)
Some want to conquer our world
The energy the rifts are giving off have awoken beings long thought fictional, such as Gaia, the spirit of the planet itself
The final rift to open leads to Hell itself and Satan(the final boss) is coming through.
You use an Psion-Sword(energy-blade) and Psion-Shield(energy shield) to fight.
You also use a variety of magic-like abilities gained from befriending certain of the boss-creatures.
You can negotiate with many supposed “enemy” creatures for trade and new skills, including just about ½ the Bosses(Fusion skills) and the Rock-Goblins and Gnolls(potions, gems, and precious metals)
You use 4 skill sets,
Personal(ex. “Hunt”, “Fish”, “Snipe”, etc…) Level-up through use
Psionic(“Psion-Sword”, “Psion-Shield”, and “Psion-Tether”) Level-up through “Upgrade” items
Fusion(ex. “Fire-Resistance”, “Aqua-Breath”, “Shape-Shift”, etc…) Level-up through use
Fusion-Combo(ex. “Glass-Storm”, “Scald”, “Sucking Mud”, etc…) Level-up through use, cannot exceed lowest level “Fusion” skill component