I have a fragment of an idea, but I am uncertain how to proceed with it. So I thought, why not ask here for advice, on the chance people read it.

The core of it is this - Having a Lannister Power Behind the Throne deck, that uses Holy characters and the Power of Faith plots.

The idea came to me, when in a tournament my opponent was playing Lannister PBtT, and by the end of his first marshalling phase he had a pair of Doubting Septa and a High Septon. Immediately I thought he was up to something, and that next turn he would flip Power of Faith, have a good chance of winning Initiative with 6, and being able to attack twice on Intrigue, then Military and Power, all without needing to kneel.

Thankfully that wasn't the case, but then I started wondering how viable it would be.

Now I know that Lannister only have two in-house Holy characters. However, there are 5 neutral Holy characters, and there is the potential to look for OOH Holy characters, the main allure being Aeron Damphair, to replace himself with more Holy characters. I could also think about characters such as Jack of All Trades or Prolific Statesmen to increase my crest potential.

Now, as well as the agenda, I see the benefit being access to cards such as Golden Tooth Mines, Lannisport Brothel, You Killed the Wrong Dwarf, and many other Lannister cards.

But, is it really possible, or would it just collapse in on itself? Would it be able to get enough Power to win before my opponent does?

Any thoughts/suggestions? Or am I just trying to force something together that just wouldn't work??

Outside of the fact that all of the Lannister/Neutral holy options besides the Doubting Septa aren't very good characters, I'd say the deck will do well.

You get access to confession, and an easy trigger for terminal schemes (with your non-kneelers) I'd say that's strong enough by itself.

Some non-kneeling tri-con's post valar will also help seal the game pretty well after the reset goes off.

I'd say give it a shot.

I wouldn't add Aeron and other out of house cards, because you need your first turn or 2 to be really strong. If you do go that route, Misinformation is really good insurance, especially with Shadows and Spiders. (I'd probably run those cards anyway.)

You need a way to deal with The Laughing Storm if you take this to a tourney, so keep that in mind.

Don't forget to add some holy characters over 2 cost, because early First Snow will be pretty common

You could certainly do it. Would it be a good deck? Hard to say. The problem is that both Lanny holy characters are fodder. The Septa especially. The Septon at 2 cost, 2 str power and int is better, but he's still a 2 cost, 2 str. Of the neutral holy characters you mentioned 1 has no icons at all. 1 is a 4 cost war/holy army with military and power but is also an ally. He would be a non kneeler with Power of Faith, but he won't have an int icon to help power your agenda and most people don't care to play 4 cost allies. The Godswood Attendant however is 3 gold for a 3 str int and power. He is still an ally, he is also a full tricon on your Power of Faith rounds, so he's not bad. If your meta tends toward ally hate he could be a risk but he'd fit well otherwise. Thoros at 3 cost and 2 str is a bit weaker than you might like, and lacks the int icon to benefit from your agenda, but he has renown, which is great on holy with Power of Faith. Last and best the High Septon will be a tricon for Power of Faith and is immune to triggered effects. Further, he can't die, if he does he just goes to the bottom of your deck and you get 2 power. He'd be the sat of your deck probably.

Point is, other than the Septon and maybe Thoros all your potential characters are lackluster at best and potential ally discards at worst. There is a reason most holy decks are run out of Bara or Greyjoy. Each of them has a holy character with printed stealth and one with renown. They also have a much bigger pool of characters to draw from. If you want to try it I'd probably build around 2 or 3 copies of the High Septon. His immunity is a huge asset. Plan to play any positive attachments on him to help further protect him from Burn and Search and Detain. x3 Doubting Septa, Practical Believer and Godswood Attendant and 1-2 Thoros depending on preference. I'm you Writ Small with it's Deadly for the phase would probably be a very strong event in this deck especially on a Power of Faith round (though not on the Septon obviously). Terminal Schemes was already mentioned.

If you can afford the cost it might be worth considering Mel OOH, she is one of the biggest boosts you can give a holy deck, either the extra power claim to speed rush or the power steal kill Mel given that you can make multiple Int challenges to trigger her.

Try it and see what you think. And if it doesn't work you can always build a Bara Holy deck with Shadow Politics and Blackwater Bay and get your extra Int every round that way.