Concepts for a Pokémon, or rather, Fakémon line for Sonic as a whole, and since I'm thinking about Shadow, he gets shown off this time. :]

The characters are as following:

Doompod
Black Arms Pokemon
Dark
Made by the hands of man, with blood of creatures that live in space. Due to where he was born, many find him staring at the stars.
Evolves at LVL 20

Darkeye
Revenge Pokemon
Dark/Psychic
Made by the hands of man. This pokemon is stubborn, only listening to those he trusts. If his allies fall, he grows increasingly angry.
Evolves at level 50

Shadoom
Ultimate Lifeform Pokemon
Dark/Psychic
No longer afraid of his past, this pokemon fights for his friends and survival. He grew attuned to the crystal at his neck, drawing power from it.

Chaos Shadoom
Ultimate Lifeform Pokemon
Dark/Flying

When handed a Chaos Crystal, this pokemon unlocks his contained power. He is a creature capable of warping time and space itself. And yet, he only uses this power to help his friends.