Introduction to Mystara?

[frog]

I second the Vaults of Pandius. This is an invaluable resource on Mystara (although I prefer it as "The Known World"). If you have a ton of $ you could also look up all of the Gazetteers (originals) or pick up the pdf files for cheap of the majority. Some of the best things ever done of their kind and what I consider a high water mark for Gazetteer type supplements. I am still missing 3 of them (Orcs of Thar, Shadow Elves, and Atruaghin Clans). At this point I don't know if I will ever complete my set...ah well, one can dream.

 

[Orius]

Never was into Mystara much really, but I'd say either the RC or the introductory 2e boxed set. The RC had some basic setting information, and might be useful to a starting DM. Same with thte 2e set, I've never read it, but it was intended at the time to be used by novice DMs, so it's probably worth using as a starting point.

Stuff like the Vaults of Pandius, the Wizards boards and so on can probably provide setting fluff once the DM gets the campaign off the ground.

 

[S'mon]

BTW I did most of my Mystara GMing with a lengthy campaign centred on the Dawn of the Emperors boxed set. The solo PC started out as a Thyatian legionary guarding the border with Ylaruam. It ran from ca 1000 AC through to 1045 AC and involved great wars, the assassination of the Alphatian Empress by her mad son, the subsequent Thyatian invasion and fall of Alphatia, the Thyatian colonisation of the Soderfjord jarldoms and the PC establishing a Norse kingdom, and eventually following the deaths of most of the Thyatian and Alphatian royal families, a golden age with the Alphatianised daughter of the Thyatian emperor Thincol married to the son of the Alphatian Empress, becoming the joint monarchs of a unified empire. All this was strongly supported by the boxed set, with its NPC descriptions brimming with usable plot hooks.

 

[BiggusGeekus]

I'm a huge fan of GAZ3: Principalities of Glantri. There was an AD&D boxed set for it (as a poster above mentioned) but I think the gazetteer is a little better, probably because it was written by Bruce Heard, the guy in charge of the Known World stuff, and he simply had a better handle on the material. That said, the boxed set was written by Monte Cook and has a great introductory adventure. Comparing one to the other is like comparing a chocolate sundae to a caramel sundae, they're both good and liking one over the other is a matter of personal taste.