If I were to design an In Nomine CCG, I would start by tweaking the rules of Jyhad / V:tES because in my opinion, it has one of the most balanced systems. In particular, rare cards are just different or outright weird, not necessarily more powerful; you actually want less of them. Common cards make up 60%-80% of any good deck. And, Jyhad had a very strong political element. It allows several completely different strategies for winning, primarily rapid bleeding, manipulative voting, and direct combat.
In another world, everything was much as our own for a great many eons, and we pick up the story shortly after humans come onto the scene…
The Eden Experiment
Humanity was dirty, cruel, and small-minded—but some angels proposed that within them they must possess a certain divinity, otherwise God would not protect them. Lucifer proposed an experiment, with which he hoped to satisfy everyone's curiosity.
The following are some rules I created for running Ethereal player character prior to the printing of the Ethereal Players' Guide. They're still an interesting, alternate take on the whole thing:
Ethereal player characters start out at seven forces, and have 150 essence to spend on vessels, at the costs given in The Marches (which can buy two levels of human vessels, or more levels of simpler vessels).
In a bar somewhere, a scruffy-looking yet somehow attractive and charming man rambles on.
"No, the whole bringing monotheism to the masses was Yves' idea, man. He thought that if we told people some version of the truth, they'd all accept it and use it to guide their lives towards positive principles…sounds reasonable, doesn't it?"
He pauses to take a drink from his mug of beer.
Somewhere, in a dark corner of an unassuming eatery, two men who are not men talk of things no true man knows. One of them is handsome, with rough black hair and a charming smile, and a rose the color of a sunrise tucked in the lapel of his loose white shirt. The other is hard to make out, wearing an elegant suit of black cloth, his face lost in the shadows, only his grinning white teeth visible, like some humaniform Cheshire Cat.
The dark one speaks first, "So, you've decided to take me up on my offer?"
"Yeah, I've had time to think about it."
Here's a little plaything from Norse legend:
The Ring of the Niflung Horde
This ancient artifact was forged by ethereals of the Norse pantheon, and was taken from the dwarf Andvari by none other than Loki himself. In appearance it is a heavy ring wrought from flame-red gold. If placed upon a finger before going to sleep, in the morning the bearer will find similar rings upon all his fingers. Each of these nine new rings is yellower in color than the original, and thus easily told apart; they have no special properties.
This particular little device is the result of collaboration between servants of Vapula and Andrealphus, though some argue that Kobal may have provided a little under-the-table inspiration. A Hormonorator appears as a fairly standard (that is, cliched) Vaputech Raygun, and its use requires the Ranged Weapon:Handgun skill. It strikes with an accuracy of +1, due to its light-speed beam, which appears as a sort of tacky pink laser. Rather than do any damage, the target suffers from some unusual physiological effects.