not a cohesive guide, but I have some strat files. it doesn't explain the game mechanics, but provides basic guidance through a first city. still figuring out the Forsaken and later cities. read the game file guides, they're super useful
basically, earlygame_earlycampaign + earlygame_turns1_12 are the first part of the game (its boring and slow) which is mainly collecting energy
then firstcommanderbreak guides you to start breaking chosen.
there's still more tricks to learn. like getting orgies, final battle breaks, which are all relevant to city 1 that i haven't documented for myself.
then there's distortions and forsaken which I haven't really learned yet.
I have some experience with distortions though I haven't messed with forsaken either. Here's a brief description based on what I've seen...
---Rampancy: This distortion makes the subjected chosen hyper aggressive and apathetic to the loss of life, often reveling in the fulfilment they feel in the destruction they cause. Gameplay-wise These chosen are one of more tricky of the 4 distortions to play around in battles. Whenever a Rampancy Chosen have a higher HATE level than PAIN level while surrounded, they will go on a rampage where they break free of the surround. They are untargetable in this state and I think they do extermination damage as well, but they are effectively out of the fight for the duration and any turns not spent during battle will be spent afterwards. If you wish to setup an orgy with this distortion active, prioritize Pain gain and develop Hate gain last to extend orgy damage on the chosen. The chosen will eventually rampage out of the orgy early, but hopefully after withstanding oodles amounts of trauma before they do. In the final battle, the distortion will deal damage to their resolve dependant on Hate levels and possible Pain levels. The more Hate levels the chosen has, the more damage they take per turn during a rampage.
---Temptation: This distorion involves developing a chosen to give in to the carnal lust they are subjected to on a daily basis. To activate this distortion, you need to do a large amount of pleasure to the chosen and then preform the special action (Tempt), afterwhich the chosen will be neutralized for the duration of the would-be surround. The more Tempts you do to a chosen over the loop, the lower the requirements become (I believe the reduction is a compounding 10% reduction; 100%>90$>81$). Tempting in the final battle will require whatever the usual requirement is x10, so if you need 10k pleasure usually, you will need to bring the chosen to 100k pleasure to tempt them. Bright side is that the Tempt here is a one hit ko and immediately captures the chosen.
---Negotiation: This distortion focuses on leveraging a chosen's desire to protect the city (altruistic or otherwise) to bring them into further degeneracy. To use this distortion, you simply need to approach the chosen and negotiate a truce with the chosen for their body. This will begin a custom sex scene but it's safe for you to immediately end the interaction once the truce is concluded. As you negotiate more truces with the chosen, they will begin to become more....affectionate with the demon lord, which directly translates into a growing damage action in the final battle. These bonuses are linear so it will go 10%>12%>14%... for one special action (you will need multiple to fully break the chosen's resolve). The drawbacks of using this distortion is that 1: Any chosen not in the same Negotiation distortion will become bitter enemies with the chosen while those that are will be best buddies, 2: you can't earn any trauma or breaks for that day as you have to honor the truce to progress the distortion, 3: I think negotiation tanks whatever trauma the chosen has built up by a significant degree and does not generate any EE from them for that day, might want to make sure you have whatever breaks you want on the chosen and energy you need before you go hard on negotiation.
---Adverse (can't remember the actual name): This distortion is my least familiar distortion though I have done it once before. This distortion basically forces the chosen to go into a catatonic state from the trauma they experience in the loop. To trigger the distortion, you need to cause an orgy for 10 turns, at which point they will become catatonic for the rest of the day, effectively removing them from the fight completely. I mean gone, outright dissappears from the target list. The more times this distortion is triggered, the smaller the requirements become. For the final battle, successfully triggering the distortion will immediately ko the chosen.