DMing my first campaign

[McMilkerton]

I'm looking to DM my first ever campaign. I've decided on the world I want to play in but I would really like to run a premade campaign that would be fitting to the flavor of the world I have made. Essentially, the world would be a planet that drifted away from the sun, causing the surface to be a frigid and nearly uninhabitable for most living things. The majority of the life forms would be creatures that live underground and I want the planet to be massive. I have an idea that there was some kind of wurm god that is in hibernation somewhere on the planet and cities and towns were built in the wake of the tunnels he dug. I want the playable classes to be only things that would live underground. I've been referencing the underdark and races of darkness. I also want humanity to be wiped out. I was thinking of starting them off at lvl 5 and would love any input I could get. If you would know of any type of premade adventure that I could adapt into this world easily please let me know!

[Avenger]

I advise against starting your first campaign at lvl 5.

[McMilkerton]

I have played d and d a lot, just never dmed before. but I think I agree. The only reason I would want to is because the players want to be higher level.

[CoI]

Playing and gming is COMPLETELY DIFFERENT. Fast track them to lvl 5 if you really want to, but start at lvl 1.

[Rub-Eta]

You're awfully specific about your setting, so I'm affraid I can't help you there. If you've played Pathfinder or 3.X before, starting them at level 5 shouldn't be a problem, though.

[Ghray]

Interesting premise, but what exactly would the players be doing? You need some kind of hook to bring them in. Maybe the wurm god was responsible for the planet being drifted? Or maybe the wurm god was saving the planet from some world eating entity (or a beacon that was summoning said world eating entity).

The only problems that I have is that your campaign is very specific and by limiting classes/races, then you're essentially preventing your players from playing what they want to play. Remember, as a DM, your job is to make sure both you and the players have as fun much as they can per session.

For example... instead of humanity being wiped out, what if the Dwarves took them as refugees and Humans now live with Dwarves?

Lastly, start at level 1. If you were an experienced DM with experienced players, I'd say start at level 3. The reason you want to start at level 1 is that at level 5 you won't know the power scale of your players. Making encounters would be really hard.

Whyyyyy not you do this. Same world, same premise, but instead you start your players at level 1 and have the world in the process of moving. Would give your players the opportunity to prevent the apocalypse around level 6, and if they fail, then what I said above can apply.

Good luck dude!

[Derek Dalton]

Everyone has been stating start at level one, I agree completely! You are inexperienced at fifth level and higher PCs start getting the more powerful abilities. If your group is understanding they will start at first and be happy.
The premise is good but I agree with Ghray about limiting classes and races. While I don't often play humans a lot of people like them. Two feats makes them attractive. There is a lot of material regarding humans surviving underground. Just about every class can be used in an underground setting, although some will be better then others.
I like the premise myself but another bit of advice since you are new try running in an established world using published modules. This is for your benefit. Depending on your group this will help prevent problems. Some players live to screw with a GM and if you are not prepared for this you will be unhappy. With modules they usually have ideas and tips that will help you deal with situations your players may throw at you. A new world is a great thing but if you lack experience it can quickly spiral out of control. Trust me seen it happen a lot.
Being a GM is hard work make no mistake! I have been a GM more then a player. I still run into problems with players even in an established world. I'm not saying don't be one. I suggest try it using established materials first before using your world. Secondly establish ground rules for your campaign and world.

[Vatras]

If you look for scenarios underground, you can use or cannibalize Rappan Athuk (a pretty large dungeon, and there is a PF version of it) or maybe go much further back to the old AD&D module Against the Spiderqueen (which you have to re-write of course). The latter consisted of four modules, the first of which was set in three giant strongholds, the second explored the way down to the drow city Erelhei-Cinlu, the third was set in the city (Vault of the Drow), and the last one explores Lolth's domain in the Abyss.

There was also a three part series for 2E, where the mindflayers plan to extinguish the sun. At least one of them had stuff about a frozen surface in it, I believe it was the second one (A darkness gathering, Masters of eternal night, Dawn of the overmind). I liked the illithid as main villains and the sourcebook for this, The Illithiad, was also interesting. Maybe worth a look, if you plan to stay underground.