Inner Earth Sword & Sorcery Campaign Using both Castles & Crusades (C&C) and Night Shift: Veterans of the Supernatural Wars (NSW) Rpg

 To create an Inner Earth Sword & Sorcery campaign  using both  Castles & Crusades (C&C) and Night Shift: Veterans of the Supernatural Wars (NSW), the Castle Keeper (CK) must blend the two rule sets and create a unique setting that combines ancient fantasy with modern horror tropes.

Core Concept: "The Hollow Earth War"

The campaign is set in a vast, subterranean world where divergent human civilizations and non-human races have evolved in isolation for millennia. This "Inner Earth" is a brutal, primal land (Sword & Sorcery) that has recently seen an influx of "Veterans of the Supernatural Wars" (NSW characters) who were pulled into a portal from the modern world. The ancient, cyclical conflicts of the Inner Earth have become their new supernatural warzone.

Integrating the Rule Systems

The key to integration lies in C&C's flexible "Siege Engine" attribute check system, which is designed to be easily adaptable and allows the CK to make rulings on the fly. NSW is also built on simple, old-school mechanics, making them highly compatible.

• Classes and Characters: Use the core C&C classes (Fighter, Wizard, Cleric, etc.) for native Inner Earth inhabitants and the NSW classes (Chosen One, Psychic, Survivor, Veteran, Witch, etc.) for characters pulled from the modern world. The NSW characters retain their modern skills and knowledge but must adapt to a world without technology.
• Attributes and Checks: Both systems use attributes (STR, DEX, CON, INT, WIS, CHA) and d20 checks. For C&C, the CK determines if an attribute is Primary (target 12) or Secondary (target 18). For NSW, checks often use percentile skills or a d6 rule of 2 check. The CK can unify this by using the C&C Siege Engine for all checks, with NSW skills providing a bonus or making an attribute "Primary" for specific, modern-world tasks (e.g., a "Computers" skill might make INT a Primary attribute for interfacing with ancient, alien technology).
• Monsters and Magic:  The C&C Monsters & Treasure book provides a wealth of classic fantasy creatures, while NSW offers modern horror monsters like vampires, werewolves, and demons. The CK can easily adapt NSW monsters to C&C by using the monster's Hit Dice as its attack bonus and determining its primary saves. Magic systems can run in parallel: C&C Vancian magic for native wizards/clerics and NSW's more flexible Arcane Powers, psychic abilities, and ritual magic for the supernatural veterans.
• Grit and Tone: Both games offer rules options for varying levels of grit. The CK should lean towards the grittier, deadlier C&C style to evoke the Sword & Sorcery feel. Combat should be fast and lethal, and magic should be powerful but potentially dangerous or taxing.

Inner Earth Setting Details

The Inner Earth is a land of wonder and peril, a brutal pre-historic landscape with lost civilizations and ancient secrets.

• Geography: The world is characterized by enormous caverns, vast underground oceans, and unique climate zones (jungles near the "poles," deserts in the interior). Travel is complicated, involving carved passages, strange river systems, and dangerous mountain ranges.
• Factions:
  • The Serpent Kings: A dominant civilization of sorcerer-priests who use ancient technology and dark rituals to control the sunless seas. They are a primary source of evil sorcery.
  • The Legion of the Sun (NSW Crossover) A secret society formed by veterans from various Earth timelines, dedicated to fighting the supernatural threats of the Inner Earth. They serve as the central hub for the players.
  • Primal Tribes: Various human and non-human tribes (cavemen, lizardfolk, degenerate humanoids) who survive in the wilderness, often worshiping forgotten gods or the Serpent Kings.
• Campaign Arc: The campaign begins when a powerful ritual or cosmic event tears a hole in reality, dropping the NSW characters into the Inner Earth. They must link up with existing factions (potentially a small outpost of C&C adventurers) and work together to find a way back to their home realities, all while fighting a new, ancient supernatural war.

Sample Adventure Hook

A prominent member of the Legion of the Sun has gone missing while investigating strange power fluctuations in the ruins of an ancient, volcanic city. The players (a mix of C&C and NSW characters) must venture into the ruins, which are infested with mutated creatures (C&C monsters like giant spiders and cave bears, and NSW ghouls) to rescue the agent and uncover a plot by the Serpent Kings to open a permanent, destructive portal to the surface world.

Creating monsters for the "Hollow Earth War" campaign 

involves using the  Castles & Crusades (C&C) 

 framework as the base and layering in the unique,

 often weakness-driven, elements and horror aspects of  

Night Shift: Veterans 

of the Supernatural Wars (NSW)

.