To start off: The Pokemon themselves! Here's how I think they can work:
- The Snag Machine, equip-able by crafting it and placing it in it's slot below the shiny charm. Crafted like so:
- Once the player has the Snag Machine, they can capture shadow pokemon. These would be either very rare wild spawns, or somewhat rare pokemon carried by trainers.
- Once caught, a player can work towards opening a shadow pokemon's heart by walking it around, using it in battle or using a Lure on it (in place of Scents). Lures matching the type of the pokemon will open their heart substantially.
- As for what pokemon can appear in shadow-form, here's a list of all of them from Bulbapedia. They all have exclusive moves, too, so it'd be a way to obtain those.
- To identify them, they could have a purple particle-y aura.
Now, to purify them. I think shadow Pokemon completion could make a nice endgame goal, so I made the recipes relatively complex and material-hungry. There would be two main methods of purifying pokemon:
1, Have Celebi in your party, as well as a pokemon ready to open it's heart. Right click an Ilex Shrine, select the Shadow Pokemon and.. boom! Purified, nice and simple.
2, The Purify Chamber.
The Purify Chamber is as follows:
- A structure the player must assemble of various parts. These include Purify Chamber Pad, Purify Chamber Computer and Purify Chamber wiring.
- A purify chamber pad is a structure that must be built in a 3x3 format. It can be crafted 3 at a time like so: .
- For each 3x3 Purify Chamber Pad the player assembles, they have access to one set with 4 slots for regular pokemon, and 1 for the shadow pokemon.
- More sets can be added by linking together pads via the Purify Chamber Wiring and placing a P-Chamber Computer at the front of one pad.
- The computer and wiring are crafted as so:
- Example of a fully-built purify chamber could look something like this:
- If the size of certain pokemon is a concern, I think having them all by Pygmy-sized "holograms" could be neat.
- Once a pokémon is purified, it gains a light-blue coloured name, and emits paleblue/white particles.
Hope the concept sounds interesting! Thanks for checkin' it out.