Interesting. Specially where you say you can choose a whole storyline among a bunch from the begin. But I guess it may be a suspense game, so it'd be better to think a complex story and not-so-obvious quests.
Now, by "Holy Force" you mean... "luck"? Jeje...
... Je, sorry, just get a little involved
... It's classic that you're safe in saving points, but that might suggest you're intending to make a random-encounter battle system, ain't you? If you're escaping from a single murderer, exactly how is player involved in a danger situation? I give an example: In Demento (aka Haunting Ground) there're nothing but 4 or 5 enemies that go all over the castle, one after another, so each one mark a whole stage in the game. You just happen to find them, and have certain items so you can fight them, or just have to look for a hiding place or run until, eventually, you miss them. If that's the idea you have, you should randomly set where has to appear the murderer, and where. If not, which other conflicts may face the player?
Hope I didn't overdo it and you may find this useful. The best of the lucks in your game.
Discord
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