From publisher blurb:
The Emerald Order is devoted to the guardianship and understanding of the mysteries of the Emerald Tablet, whereon the greatest arcane secrets of Thoth-Hermes are inscribed. The inner circle has divined the secrets of the tablets, enhancing their already formidable magical abilities with new understanding.
Demon Cults: The Emerald Order includes:
A new cultist prestige class, the Emerald Disciple
Fully detailed cult leader with complete stats (CR 12)
Plots and adventure hooks for party levels 1 to 12
New magic items including an emerald shard ioun stone and the Emerald Tablets artifact
A new smaragdine golem, fully illustrated
Give your villains a little arcane boost. Show your players a new challenge with Demon Cults: The Emerald Order today!