Every card will have a name, mana cost, Type and Sub-type, optional keyword (flying, first strike, etc.), ability, and flavor text.
It's free, because charging money for shit like this is silly. All I need from you, if you're interested, is your character's name, a picture (preferably with a background and who drew it), a little blurb about him/her/it (to get a sense of what their ability should be like), and maybe a quote for the flavor text.
I don't claim to be an expert on game balance, but I the focus here is on flavor, not necessarily practicality.
Examples:
