O2xygen (First Person Cave Exploration Horror)

Concept

O2xygen is an atmospheric first-person adventure game where players embark on dangerous cave expeditions across the world. Whether exploring jagged mountain caves or deep underwater caverns, players must balance survival mechanics—such as oxygen and sanity—while uncovering hidden treasures, archaeological wonders, and supernatural mysteries. The game blends immersive survival elements with horror-like tension, as players face unseen threats, mythical creatures, and the ever-present dangers of the environment. The balance of realism and supernatural horror keeps players on edge, making every dive into the abyss a high-stakes adventure.

Core Gameplay Loop
  1. Preparation
    • Choose equipment from the RV (land-based) or boat (sea-based).
    • Plan expeditions based on environmental hazards and known cave challenges.
  2. Exploration
    • Navigate diverse cave systems: above-water, submerged, or hybrid.
    • Encounter dynamic obstacles, from tight passageways to shifting terrain.
  3. Survival
    • Manage oxygen, health, and sanity while contending with environmental dangers.
    • Utilize tools and equipment to overcome obstacles and evade threats.
  4. Discovery & Return
    • Retrieve valuable artifacts, lost expedition logs, or supernatural evidence.
    • Return to base, log findings, and upgrade gear for deeper explorations.
Hub Area (RV / Boat)

The player’s base serves as both a safe zone and a progression hub.

  • Equipment & Upgrades: Improve diving gear, sanity aids, and survival tools.
  • Mission Planning: Choose caves to explore, review expedition data.
  • Statistics & Sanity Tracking: Analyze past journeys and monitor the mental toll of expeditions.
Cave Types & Environments
  • Above-Water Caves: Tight, dark passageways requiring climbing and endurance.
  • Underwater Caves: Deoxygenated zones demanding careful navigation.
  • Hybrid Caves: A mix of dry and flooded sections requiring quick gear swaps.

Hazards include cave-ins, whirlpools, unstable ledges, and supernatural distortions.

Survival Mechanics
  • Sanity Effects: Lower sanity causes auditory/visual hallucinations and alters player perception.
  • Limited Equipment: Players carry only four main items, forcing strategic choices.
  • Primary Stats:
    • Health: Depletes from injuries or attacks.
    • Oxygen: Limited supply for underwater traversal.
    • Sanity: Affected by isolation, darkness, and supernatural encounters.

Low sanity can lead to hallucinations, flipped controls, or fatal missteps.

Enemies & Threats
  • Invisible Entity: A stalking presence, audible but unseen, increasing paranoia.
  • Wildlife: Cave-dwelling predators reacting to player actions.
  • Mythical Creatures: Guardians of lost relics, requiring strategy or avoidance.
Gear & Equipment
  • Lighting Tools: Flashlights, flares, glow sticks for navigation.
  • Diving Gear: Oxygen tanks, fins, wristwatch O₂ tracker.
  • Climbing Tools: Ropes, ziplines, specialized shoes for vertical traversal.
  • Survival Tools: Spray paint for marking paths, bells to gauge depth, sanity-restoring items.
Inventory Management System (IMS)
  • Weight-Based Carrying Capacity: Players must manage inventory strategically.
  • Realistic UI: Inventory appears as an in-world device (OMNI interface).
  • Drag-and-Drop Equipment System: Easily swap, use, or inspect gear.
  • Crafting Integration: Unlock blueprints and assemble survival tools on the go.
Expedition Challenges & Progression
  • Increasingly dangerous cave layouts with more complex puzzles and hazards.
  • Deeper expeditions introduce sanity-draining environments and hostile entities.
  • Unlockable gear and advanced survival tools for prolonged exploration.
Narrative & World-Building

Each cave tells a story—ancient relics, forgotten explorers, and cryptic markings hint at a deeper supernatural mystery. As players push further into the unknown, they unravel a secret far greater than lost treasure.