Game Design Document
Experience
I want to counterpoint RPG style minmaxing and power fantasy with a feeling of being shunned for becoming more and more of an outlier. To that end, various shopkeepers and NPCs will begin to avoid you as you collect spirits, leaving you with the hard decision of giving up skills to continue receiving services.
Mechanics
There are three primary mechanic concerns:
Combat
Combat will be a shoot-em-up style top down game. Each encounter will be an arena style combat with one or more enemies, one of which is the goal. Defeating this creature spawns the spirit that you add to your collection.
Enemies can have several states, special weaknesses, or weak points. Their attacks can vary greatly from battle to battle.
Equipment
There will be "basic" equipment that lets you tune your stats to match various enemies, but the amount of customization is limited.
Once you get spirits, they become available as special equipment that have higher stat changes and provide special behaviors.
Aid
To change some of the assumptions RPG style games have, remove currency as a resource, and leave the standing with NPCs the only access to various aid.
This includes the armorers, the inn, alchemists, mages, doctors and other out of combat aid.