There are a number of rules unique to this game that sit on top of the 5e open-source rules. These rules are found below.

• The core mechanic is very similar to 5e
• A simplified action economy
• Unique character generation rules specific to the Eldritch Earth setting
• Combat related rules and clarification
• Healing and damage and rest information collected in one place.
• A corruption system to track demonic possession
• A very simple but effective sanity system
• Custom rules with regard to recruiting NPCs and retainers along with details on morale and command.
• An innovative but OSR-flavored rewards system
• A new spellcasting library that captures the flavors of Eldritch Earth by making spell failure more regular and more difficult
• A spell concentration rule that is similar to that introduced by 5e
• A master list of potential conditions a creature might suffer
• Equipment that can be broken, repaired, and has an encumbrance rating
• A interesting mechanic for tracking one's supplies

• A simple description of regular expenses and maintenance
• Directives for how to buy and maintain property and strongholds
• Rules for downtime crafting of mundane and magic items
• A catalog of books one might acquire for various magical and mundane needs
• Information on how to request and carry out downtime side quests
• Details on how to use the "Western Marches" style campaign