(heavily edited at 12:16pm Central on Sept 7, 2022)
Hi @Valamas!
I am very familiar with the nuances of Civ6 religion, so maybe I can help you guys out.
In order to declare war with the Holy War casus belli, a player must have a city that was converted from their own religion to a foreign religion. However, with this gameās rule āNo unit can enter another players territory unless at warā the foreigners cannot enter your territory with their missionaries/apostles to convert your cities. This creates a rules deadlock.
I think the way out of this conundrum is to make an exception for all religious units (missionaries, apostles, gurus, inquisitors) to enter foreign territory at all times. Since you have the āRemove Condemn Hereticā option selected from my mod, the only way to kill an opponentās religious units is with your own. (Inquisitors are good cheap defenders. Otherwise you need apostles.)
{important side-note: even though you selected āRemove Condemn Hereticā watch out for barbarians, city-states, and AI enemiesā¦ the computer can still condemn heretics (that is, they can instantly kill religious units by walking on them with a military unit)}
Then once you manage to convert a foreign city, youāre at risk of being invaded with military troops via a Holy War casus belli. That probably wonāt ruin you, because after 15 turns you have a rule that forces them to accept peace, but itās still uncomfortable to be in a situation where youāre at war every other 15-turns.
Finally, another potential issue I see in this game setup is that once a playerās religion is no longer the dominant religion in any city (and he doesnāt have enough religious units to make it dominant anywhere), he has no realistic chance of reviving that religion. {Edge case: slight chance of being able to revive it with Warrior Monks using the āDisciplesā promotion or Vatican City suzerainty.} Thus he would be stuck continuing to play his civ as a lame duckā¦ with no possible chance to win. At that point perhaps the rules should force him to turn it over to the AIā¦ OR consider a caveat that when a playerās religion is completely wiped out he no longer has to accept peace. That way he can play on as an eternal belligerent against the player(s) who converted his cities away from his religion.
To win a religious victory you need to convert 51% of the cities in every living civilization. So itās possible to win without completely wiping out any other religion. If you let them keep their religion in just one city, they wouldnāt become an eternal belligerent.
Iām curious to hear how this game plays out! If you want to discuss anything further, just let me know.
Kind regards,
DB