The first adventure should be the one that explains how all these people from different corners of the world with violently opposed ideologies even teamed up.
Read their backstories and think how you can solve this.

>>46651188
I was thinking of starting in one of the last big metropolitan cites and let the players determine their reasons for themselves.

>>46651232
>New players
Chances are they won't create their own back stories. Force 'em into one. An easy one is they all know someone they all respect regardless of their creed.

>last big metropolitan cities
Are we talking post apocalyptic here? Have them retrieve some ancient piece of technology, a la Fallout 1.

>>46651314
I'll mkae them think of something most of them seem to have read about my made cultures within the world so that's good also its not really post apocalyptic its more like the start of a dark age where a large and continent pacifying empire is crumbling like in the 5th century in europe. So there aren't many large cities left.

The barkeep of your favorite tavern would consider it a personal favor if you'd investigate the shadowy figures and strange noises coming from a ruined homestead nearby his own. A number of livestock animals have gone missing and most recently a young boy who played with the barkeep's son.

Upon investigation, the party stumbles upon an unholy cult's black mass in the expansive cellar beneath the burnt-out old farmhouse. To defeat the acolytes and their dark priest of demonic prophecy, the party will need to outwit their traps, silence a watchman or two, destroy the blood-soaked sacrificial altar, and rescue the local child. Murdering the cult wholesale is optional but likely.

In the process they should find (either on the bodies of the cultists or displayed prominently on the altar, depending on how they are playing it) an out-of-place sort of noteworthy little trinket with a curious quality to it that can serve as the Macguffin for the next adventure. This should be of your choosing, and will hopefully be odd enough to cause the players to seek advice or information that would lead them to the next plot hook. A holy symbol of another church, maybe, or a set of tools that are hard to identify inside an ornately-decorated leather tool roll, or a crown with a distant baron's symbol, or a stone that feels warm to the touch and radiates a faint red glow, etc etc. Whatever. Something clearly unique so it catches their attention and leads them to their next adventure.

>>46651458
That sounds pretty good actually so a dark cult which is trying to summon some ancient god or something maybe ?
Maybe I could also make it so that certain rich people are into this cult and stuff which could make things harder for the party.

>>46651509
It can be as big or as little as you like. Depends on the scale of the game. You can have it be an open and shut case of a small-time solitary cult dedicated to some dark being (real or imagined), or you could have it be a single cell of a much greater secret cult favored by some of the world's rich and powerful behind closed doors -- people who would not take kindly, down the road, to the PCs destroying an altar to their dark lord.

Up to you and your game.

You can always make it seem like a simple thing and then later on drop hints that maybe there's more to it, if you run out of other ideas.

>>46651655
I don't plan to make it a government conspiracy or something but maybe a small cult of bored/fascinated rich people could work also I was thinking maybe to summon this god that these people would need a certain item then I could send the group all over the world.

>>46651416
Are people moving out of the city because it's no longer sustainable?

I think a similar thing happened to Rome once, it became a virtual ghost town full of ruins, surrounded by an actual necropolis with less than 10% of its original population. You can also have public works failing to take place because there's no money left, so no sanitation or roads or law enforcement. People get sick of it, move out and go back to their family village or start a new town somewhere else.

>>46651723
I was thinking along the lines of invading barbarians which all started with one group leaving their plagued homeland.
Then the rest got pushed around and started raiding the empire which caused ofcourse military expenses and taxes to go through the roof and peasants to escape the cities to become farmers and the like.

>>46651777
Sounds good to me. Urban decay is just cool as fuck.

>>46651793
True I'll ofcourse include gangs and stuff in the cities making everywhere unsafe and stuff like bridges,roads and aquaducts neglected.
But thanks guys I'll go with the bored rich people worshipping a ancient banished god maybe into a stone or soemthing which needs to be collected and assembled to release the god.