From the introduction:
[The Maztica Campaign Guide] is designed to attract new players to the Mesoamerican based setting known as Maztica. Maztica is a region of the greater world of Toril from the Forgotten Realms. It was originally introduced in 1990 with the novels Ironhelm (1990), Viperhand (1990) and Feathered Dragon (1991); each written by Doug Niles. It was subsequently followed up by a number of 2nd Edition gaming products, starting with the Maztica Boxed Set in 1991 (also by Doug Niles) and followed by two adventures (FMA1 Fires of Zatal by Jeff Grubb and Tim Beach, FMA2 Endless Armies by Jeff Grubb) and one accessory/adventure (FMQ1 City of Gold by John Nephew and Jonathan Tweet).
In later editions of Dungeons and Dragons, with a few minor exceptions, Maztica was summarily ignored or outright removed from the Forgotten Realms setting. With the advent of 5e and the Dungeon Master’s Guild, Maztica is back once again in the Realms!
Includes the introductory scenario "Dark Mound".