Ever since the release of David Szymanski’s 2022 indie hit Iron Lung, fans of quickfire submarine horror have been waiting for the gaming landscape to properly embrace its unique brand of claustrophobic, vehicular terror. Despite that game’s critical acclaim and its subsequent journey toward a film adaptation spearheaded by content creator Markiplier, surprisingly few developers have picked up the baton to explore similar concepts of navigating isolated, deep-sea vessels through pitch-black, terrifying environments. While other titles have touched upon underwater survival—such as the multiplayer chaos of Barotrauma—or job-based cooperative dread like Kletka and Shift at Midnight (both of which draw heavy mechanical and atmospheric inspiration from multiplayer sensations like Lethal Company), they ultimately offer vastly different gameplay loops and tones compared to Szymanski’s minimalist masterpiece.
It is precisely this gap in the atmospheric horror genre that makes The Temple such a fascinating project to watch. Developed as a total conversion mod for Valve’s legendary 2004 shooter Half-Life 2, The Temple adopts the core concept of piloting a vulnerable, cramped submarine through dangerous waters, but it dramatically expands the scope by incorporating two additional forms of transportation. By taking players out of the abyssal depths and launching them all the way up into the upper atmosphere and eventually deep space, the mod promises a multi-tiered sci-fi horror journey unlike anything typically built within the Source engine modding community.
The narrative and exploratory framework of The Temple places the player on a mysterious, aquatic alien planet dotted with bizarre, monolithic concrete megastructures stretching up from the waves. To uncover the secrets of this desolate world, players must master three separate vehicles, each designed for a different layer of the planet’s hostile ecosystem. The submarine allows for navigation through the crushing darkness of the ocean floor, while a specialized airship gives players the means to explore the turbulent skies and investigate towering, abandoned structures jutting out of the water. Finally, a functional space shuttle enables interplanetary transit to the bleak asteroidal moons orbiting the distant planet, creating an expansive playground for environmental dread.
The project’s origins trace back to a much smaller scale. The Temple was originally released as a pair of standalone maps for MapLabs, a well-known community modding initiative that aggregates custom-built levels from various Source engine mapping competitions. While that initial release was remarkably concise—offering a tight, atmospheric experience lasting roughly 20 minutes—the upcoming total conversion aims to completely revamp and heavily expand those two foundational maps. Furthermore, creator Klems is adding an entirely brand-new third map to the package, bringing the total estimated runtime to over two hours of dedicated, exploration-driven sci-fi horror.
A recently published trailer offers a comprehensive look at the mod in action, showcasing all three vehicles as they navigate their respective environments. For a project rooted in the architecture of a decades-old game engine, the mod looks remarkably accomplished, demonstrating a keen artistic eye for colossal, awe-inspiring, and deeply unsettling structures. Beyond its impressive scale and vehicle mechanics, The Temple incorporates classic psychological horror tropes, featuring invisible water-based monsters reminiscent of the stalkers from Amnesia: The Dark Descent. Adding a unique narrative layer to the desolation is a talking crow—or at least, an avian entity whose corvid language players can somehow understand—which acts as an enigmatic guide through the eerie environment.
These distinctive design choices have generated considerable excitement within the PC gaming community, drawing attention from players eager for fresh narrative-driven horror experiences built within classic engines. While there is no exact calendar release date locked in just yet, the creator has indicated that the mod will launch very soon, potentially arriving as early as next month.