From publisher blurb:
Welcome to the Iskandar Explorer's Journal, your essential guide to a magical new world!
Each volume contains fantastic new content for the Iskandar campaign setting. Intriguing lore, exciting adventure seeds, unique player options, wonderous treasures, challenging encounters, and more! Whilst the spotlight is on the world of Iskandar, this material will enrich any Fifth Edition campaign. Embrace the call to adventure and let the Iskandar Explorer's Journal be your guide!
In Volume 4, you will find:
Adventures in Rulk Majier, the Isle of Sorcery
New player options (Entling ancestry, Radiant Soul Sorcerer, and six new backgrounds)
More Treasures from the Emporium of Wonders
Salt Road Encounters
The Tale of Lord Jahn the Fortunate
Tanbour
The Master Spellbook
New Factions
Fantasy Bookshelf