I would love to hear more about your game concept!
(Psst, you accidentally put your reply INSIDE the quote. ^^())
I haven't really fleshed out any of the story
ideas yet. Being that I'm primarily an engineer, and creative writing is just a hobby that I don't do enough, I've been focusing on the game mechanics more than the plot.
Mechanically speaking... It's a turn-based RPG with a top-down, procedurally-generated map. I'm considering making it purely use equipment progression instead of levels, but I'm not set on that.
The key game mechanic is a multiversal portal invented by the protagonist, who doesn't know what to expect on the other side or really even how it works. Through the course of gameplay, you find rune stones that interfere with the "home" side of the portal, bending its destination into other splays. Each rune stone is connected to some conceptual signifier, making the portal point towards splays exhibiting that concept, but too many rune stones in proximity to the portal causes it to not work at all. (Mechanically, the runes influence the parameters to the world generator, which is also seeded with a unique value, so every playthrough is different.)
Instead of having the plot presented to you, it's more of an exploration game. The people you meet in the splays that you visit tell you about what's happening in their world, and as you progress to later rune stones, the stories are increasingly troubled, with a common thread of darkness and corruption and monsters from another world. Researchers you meet along the way (in some sense, parallels of the player) have theories and information about it.
Eventually you will find the set of rune stones that points the portal to the big bad's home splay where you can solve the problem at the source.