City Eater | Devpost

Inspiration

My primary inspiration for CityEater was from the Hole.io: You play as a black hole with an insatiable appetite. I wanted to bring this "eat the world" mechanic to Meta Horizon Worlds, specifically focusing on the mobile experience to see if I could replicate that addictive, competitive gameplay loop on a handheld device.

What it does

CityEater is a multiplayer mobile game where players control a moving black hole. You start small, consuming street signs and fences. As you "eat" objects, your black hole grows in radius, allowing you to consume larger assets like small houses and eventually buildings. The goal is simple: consume as much of the map (and other players) as possible before the time runs out.

How I built it

I built this project solo using Meta Horizon Creator and Visual Studio for Typescript. As an Unreal Engine developer, this was totally new for me.

Challenges I ran into

Going from Unreal to Meta Horizon came with some difficulties:

The "Hole" Illusion: Without custom shaders to handle vertex displacement (masking objects as they fall), I had to script the physics manually to make objects appear to fall "into" the ground.
Networking & Replication: I encountered a critical bug where attaching the black hole entity directly to the player caused ownership and replication conflicts.
Performance: To solve the replication issue, I had to set the black hole's location every single tick. While this fixed the bug, it introduced performance overhead that I am working to optimize.
Solo Development: Building a large city map alone while learning TypeScript was a massive undertaking.

Accomplishments that I'm proud of

I am incredibly proud of the map scale. It is the largest environment I have built by myself. Furthermore, successfully publishing a playable multiplayer build on mobile despite the steep learning curve of a new engine was fun.