An underground subversive cult that views animates as God's final mop up. The ongoing efforts of people in authority to stem the tides of destruction are an abomination and a direct contradiction of the will of God - that all peoples should be harvested for the final judgement.
Obviously for the Church of the Rapture folk to still be here is because either they need to redeem their souls sufficiently for the Rapture - or that the world is too corrupt for it to occur properly.
This terrorist group spends its time reducing the defences of the city. From blowing up walls, to assassinating members of the Deathwatch.
Confronting any member of this Church is much like talking to a member of the Westboro Baptist Church.