We should be able to fight apostles that are hiding in their cities or [...]

[Bliss]

[...] at least, make them lose health for staying inside a city that is following another religion. This way, the player trying to push a religious victory wouldn't be forced to declare war on players using this (feature?). Instead, players wanting to stop another player's Religious Victory would have to declare war on him and use the remove heresy option.
When pressed against other types of victories, losing players always need to take action and do something to stop the winning player, however, in the RV scenario, it is the opposite. You did all the conversion right, but you still need to declare war on a player sheltering apostles.

 

[Ciarson]

how about remove the button to use a charge?

instead the apostle need to move (like attacking) on the city. if there is a religious unit inside, the religious unit would be attacked first. effect could be reduced by wall as the apostle could be prevented from entering the city if open border is not effective.

NB: could be done the same for military unit. wall still doing their "damage reduction".