X10’s poster map served a dual purpose as both an overview map and a game board for the adventure. It was the first map to show the whole Atruaghin Plateau, confirming how the X1 and X4 maps join together. It also introduces Sayr Ulan, a new city in the Sind Desert that would later become the capital of the nation of Sind, as well as capitals for Alfheim, Atruaghin, Ethengar, the Five Shires, and Rockhome.
Not content with the massive land expansion of 1984 in previous modules from X4 to X6, X7 instead expanded into the ocean itself, providing a wonderful view of the land beneath the waves of the Sea of Dread.
Depths were not marked on maps again for another few years, and this map remains one of the two best sources for the undersea layout of the region, the other being 1990’s PC3.
Continuing 1984’s mega-expansion, X6 detailed the lands south of X4’s Great Waste. Known in X6 as the Wild Lands, this region later came to be called the Serpent Peninsula.
The map was seminal in its own way: it marked ocean depths for the first time in a Mystara map. This was continued in some later maps, but often in a less obvious way, such as with textual depth labels rather than shading.
The Western Thanegioth Archipelago came as a shock to some, as it now turned out that the Isle of Dread and its archipelago were less isolated than they had at first appeared to be.
Finally, Slagovich makes its second appearance, this time along with the wonderfully banal Mule Beach and Sea Camel.
The Serpent Peninsula was revisited in Dragon 170 and further detailed in Champions of Mystara, though it saw less expansion than other areas, and always remained an area of wild lands.
This is the seminal, iconic map from which the world of Mystara was born. It introduces all of the now-familiar Known World countries. What it lacks in detail, it makes up for in sheer potential — which thousands of DMs have taken great advantage of over the years, and later supplements expanded and built upon wonderfully.
The map appeared as a two page spread in X1. 1983’s reprint added a few missing names (most notably Alfheim) and smaller towns (such as Threshold), while the Expert Rules Set (1983) reproduced the northern half of the map on a single page, cropping the Sea of Dread and the Thanegioth Archipelago while adding trails and a few other details.