Then you're trying to make FGs even more OP? They're already hard enough.
I wasn't aware it was impossible to rebalance the decks of old AI as new content is added.
Aren't we going to have to do that anyway as we keep adding more content? The idea is to add more personality to the FG's not make them more powerful. I mean they are the hardest part of the game I'd expect them to have the most uniqueness. I haven't even put forth a card idea with the exception of the one I posted in response to you which was as much off the top of my head as I assume yours was.
The idea is a signature and unique card for each God. As Master of Darkness I assume you you Dark cards a lot probably more than the majority of if not all players. As such I would expect that your decks have certain quirks and concepts built in that a player who simply picks Dark as their starter element can't hope to have. Why would your deck have this uniqueness because you have spent so much time with Darkness.
The same is true for FGs they presumably will have spent a long time mastering their style of play and as such would have developed the same uniqueness and could do so in the form of this signature card. As a Master if you were an AI I would expect you to have a unique card like say maybe Soul Harvester? The same is true of an FG you would expect them to have this uniqueness and personality.
I'm not trying to suggest an uber strong card I'm suggesting a signature card, kind of like a mark card win you see it you know you are fighting someone who has won a tournament. Is is truly that much better than a tower probably not, but it is a signature.
Would a card that you could only win from a single FG be powerful? Probably. But I haven't truly suggested a single card simply suggested that each FG could have one.
After all you have one in the forums, don't FGs deserve one in game?