There are a few Planescape Introductory Adventure threads around, mainly Desire and the Dead. While I like these, I want a little something different for my campaign. So I was thinking about Wolfgang Baur's recent Planar Adventures article in Dungeon #147. More specifically his "Easy Road to Hell" adventure idea.
I was thinking we could flesh that out a little bit. Here's my idea: The PCs join together at the beginning of the adventure, to be more able to survive the dangerous streets of Sigil. Then they get a few short quests from various NPCs. This part of the adventure introduces them to Sigil.
Then is where things start to get truely interesting. A hound archon or some other celestial tells the PCs he has a job for them. They have to take a message through a portal. Unfortunetly, the message is for an Archduke of Hell. And the portal is to Avernus. Fortunetly they have a safe conduct pass, that should, theoretically allow them to get to the Archduke unmolested. Unfortunetly a lot of people want that pass...
So could you help me put together this adventure?
What CR are we talking about here? It seems a bit dubious that low level adventurers (who don't really stand out from the general rabble swarming the City of Doors) would get entrusted with such an important message. To an Archduke no less... I suggest sending that message to someone less prominent. There are plenty of lesser nobles, gods, proxies, vassals ect. in Baator that could be the target of such a message.
Nevertheless the idea is good. I'd be glad to help... Just point out with what.