Here's what I have so far:
The card game is based the color wheel.
Blue, Red, and Yellow are the Primary Colors.
Green, Orange, and Purple are the Secondary Colors.
Black, Brown, and White are the 'others'.
Blue - Water - Healing, Purity
Red - Fire - Destruction, Burning
Yellow - Earth - Defense
Green - Life - Creatures, Plants
Orange - Construct - Permanents
Purple - Sky - Spells
Gameplay:
You start your turn by drawing a card, then you can place a base color 'supplier' into play.
To get a secondary color into play, you'll need to use its two corresponding base colors.
White is from one of each base color.
Brown is from one of each base and secondary color. (or just secondary color?)
Black is from sacrificing one of each color.
^ Just some random thoughts.
Would you like to help expand it some more?