Merge Defense: Zombiez!

Inspiration

With the ongoing success of merge games across mobile and PC, I wanted to create a mobile merge-defense experience inside Meta Horizon that is fast and full of personality. I love combining two opposing ideas together into one memorable project and this game was the perfect way to do just that.

What it does

Players battle 35 waves of increasingly difficult adorable zombies, by merging through 35 levels of cannons and strengthening their defenses. After defeating Maddy Scientist's hoard, players rebirth with customized difficulty.

How we built it

Merge Defense was built in the Meta Horizon Desktop Editor and powered by over 15,000 lines of TypeScript. Every art and UI element was hand drawn in Procreate and assembled them in Canva to ensure the visuals are polished, readable, and totally custom. To speed up iteration while still delivering a handcrafted final product, I used Meta Mesh Gen AI to prototype early zombies, cannons, and layouts, and Audio Gen AI to create all sound effects and voices. The result is a seamless mobile experience that feels great every time you tap, merge, or level up.

Challenges we ran into and Accomplishments that we're proud of

Balancing art quality and performance inside the Horizon editor took careful optimization and a ton of testing. Converting AI-assisted prototypes into polished final assets while scripting every interaction and gameplay system pushed my skills in the best way. Those challenges helped me build something I’m truly proud of.

What we learned

I learned so much about pacing, animation, and building progression that works for different kinds of players. Some people finished the game faster than expected during early access, so I added 10 additional cannons and 10 more waves of zombies to extend play time. I also redesigned the original cover art after noticing players didn’t connect with it at first. One huge highlight has been seeing an average playtime per user of over 15 minutes, which tells me the core loop is engaging and rewarding.

What's next for Merge Defense: Zombiez!

I’m continuing to expand Merge Defense with new locations, additional cannons, more zombie types, and seasonal events. Live-ops packs will include limited-time collectibles, new challenges, and more leaderboard excitement, giving players lots of reasons to return and compete.