The game mentions spirits in plural, with each body of water having its own spirit, each stretch of forest having its own spirit (there's an in game incantation for greeting the local spirit before going to sleep when traveling, for instance).
Hmm, I did not realize that. I thought the spell for the local spirit that you make before sleeping was for a tontuu of some sort, although I can't recall why. I was under the understanding that there are major spirits, or possibly more aptly referred to as 'gods', that have influence over all the world, and then lesser spirits such as the water spirits you mentioned which may have influence over a certain region. Perhaps I should proceed with the usage of the term 'god' or 'goddess'?
From that perspective, I'd see a vengeful spirit of the water to be the spirit of a particular body of water, so the dangers would be present only there. Said spirit would ensure the fishing luck was abysmal, swimming within its domain would result in poor swimming results, currents that oppose the swimming direction, cramps, and possibly getting bitten by pikes (the game does have swimming result rolls, but no currents, cramps, or pike attacks). Trying to use a craft on that body of water might require more work than it should due to currents and the craft might capsize (neither present in the game currently). Walking on the ice might result in falling through despite the ice really being thick enough for an elk to run over it.
I realize not everything will happen in-game, I can take liberties with the story, usage of the game is mostly for the sake of inspiration as well as screenshots.
However, the spirits of the game are fairly simple creatures (mechanically, anyway), that forgive past transgressions if you provide them with sufficient offerings or simply let time pass. Of course, a story version might reject the offerings or demand some particular compensation. If you want a story to match the game you should probably play enough to meet them (I believe they're called the water folk in the game).
You harbor a very good point there, I have played a lot of the game but I have a very bad habit of starting over frequently so I haven't gotten particularly far in a single save file. I was not aware until recently that you could even meet the spirits at all. Are the water-folk the only spirits you can meet?
UrW magic is usually subtle. So subtle that you can't actually tell if it exists at all or if it's just luck. Did the ritual have the desired effect, or were you just imagining it did? Anyway, it doesn't harm to perform the rituals, as they generally don't cost much in materials and effort (there are a few exceptions).
I know that URW magic is typically more subtle, but as this is from the perspective of the spirits/gods I believe it'd make sense to understand their abilities and such both in and out of the game, as while I am inspired by the game, the story did not take place in a game, if that makes sense? The characters believe it's real, so I cannot make the excuse that "I didn't flesh out this character because the game didn't tell me anything about them".
Post added while the above was written:
You anger the spirits by taking without offering compensation, so fishing a lot without offerings will put you on a bad standing with the water folk, killing a lot of animals, cutting a lot of trees, and setting a lot of traps are all actions that affect the spirits of the forest negatively. However, I doubt anyone has made a tool to hack the standing with the spirits (the information is obviously stored somewhere in the save).
Understood, so angering the spirits would take a fair bit of time, and cheating it is currently unknown territory. Thanks for the information.
I believe I've gotten everything I need out of this thread. I'll leave it open in case someone has something they would really like to contribute (and because I have no idea how to close threads, or if it's even possible for me to do.) That said I think my main questions have been answered, thank you all for the lovely insight and resources.