The Floor Is Lava

Inspiration

“The Floor Is Lava” was one of my favourite childhood games—we’d imagine the floor turning into lava and jump across sofas, chairs, cushions, or anything we could find to reach a “safe zone.” When the competition began, I wanted to challenge myself by building a full game despite being new to Unity and spatial development. Recreating a childhood imagination inside mixed reality felt like the perfect blend of nostalgia and technical ambition, so I settled on bringing this simple but universally loved idea into a real playable MR experience.

What it does

The current build places a dynamic lava surface across the floor using Passthrough so the player still sees their real room. It highlights safe objects with a blue halo and spawns collectible coins on top of them. The intended full experience is a survival-style traversal game: the lava would slowly rise toward the user’s feet, coins would appear along the path, and players could use those coins to unlock helpful tools like a “freeze ray” to temporarily turn parts of the lava into ice or throwable pillows that create short-lived platforms. The long-term intention is to turn everyday furniture into interactive gameplay elements, letting players physically move, jump, and plan routes across their real environment.

How we built it

The prototype was built in Unity using the Meta SDK. I integrated Passthrough to render the real world and applied a shader-based lava texture that covers detected floor surfaces. I also created a basic system for identifying “safe” surfaces and overlaying the glowing blue halo. Coins are spawned on these objects and rendered above them to encourage exploration. Most of the work focused on understanding Unity’s workflow, building a stable MR setup, and stitching all components together into an interactive loop.

Challenges we ran into

This was my first time working with Unity, so even the initial setup—understanding scenes, prefabs, build pipelines, and XR rig configuration—took significant time. Integrating the Meta SDK was another major hurdle; getting Passthrough, scene understanding, and object rendering to behave consistently was tricky. Creating interactive mechanics on top of this (like moving platforms or rising lava) proved challenging within the limited time.

Accomplishments that we're proud of

I’m proud that despite being completely new to Unity, I managed to get the core building blocks working:

• Passthrough integration so the room renders correctly.
• Lava visualization mapped onto the real floor.
• Safe-object detection with halo effects.
• Coin spawning and rendering. These give the project a functional foundation that can be built into a full MR game.

What we learned

The biggest learning was how deep Unity’s ecosystem really is—scene systems, physics, rendering pipelines, XR components, and SDK integrations all interact in complex ways. I learned how to work with Meta’s Passthrough APIs, how to synchronize virtual content with physical surfaces, and how difficult but rewarding it is to translate a simple idea into spatial gameplay.

What’s next for The Floor Is Lava

The goal is to polish the prototype and implement the full intended mechanics: rising lava, freeze-ray tools, destructible pillow platforms, better collision logic, and more interactive traversal elements. With more time, I want to turn it into a complete, fast-paced mixed-reality experience where your own room becomes the playground.

Built With

• unity