Kawaii's Merge Kitties

Inspiration

I was inspired to create Merge Kitties as both a personal and creative challenge—to see if I could design and publish the first mobile-only merge game in Horizon Worlds. I love building games, and each new project is a chance for me to step outside my comfort zone and try something I’ve never done before. This time, that meant developing a game built specifically for mobile, with a vertical layout, simplified touch interactions, and gameplay that feels fun and satisfying whether played for a few minutes or a few hours. I looked at a range of cozy mobile merge games to understand what made them work—how they balanced simplicity with long-term goals, used satisfying progression loops, and created a relaxing, low-pressure environment for players. But more than anything, I was inspired by the 40+ games that make up my own Kawaii Universe. I wanted Merge Kitties to feel like a natural extension of that universe: colorful, charming, and connected. Some of the cats in this game also appear in Kawaii’s Kitty Care Café and the Meow Magic update in Kawaii’s Grocery, helping to create a sense of continuity and emotional connection across my worlds. By reintroducing familiar characters in a fresh format, I hope to encourage long-term player retention while building out a shared experience that feels personal and rewarding.

How we built it

Merge Kitties was built entirely in the Meta Horizon Desktop Editor and fully optimized for vertical mobile play. Since Horizon doesn’t currently support native portrait orientation, the entire game had to be constructed rotated 90 degrees—a creative workaround that made layout design and spatial planning much more complex. I followed a “design, test, iterate” development cycle with a strong focus on mobile-first considerations like thumb-reach, tap accuracy, and UI clarity. Frequent mobile playtesting helped refine gameplay pacing, screen flow, and user experience to ensure the game felt intuitive and fun across a variety of devices. To bring the world to life, I used a range of tools that supported the visual, audio, and UI design. All kitties and accessories were designed, hand-drawn, and animated in Procreate, giving the game a cohesive and on-brand visual identity. Blender was used for preparing and importing assets, and Canva helped create clean, touch-friendly UI elements and promotional graphics. Custom sound effects were created using Horizon Sound Generator to add charm and feedback to interactions. All scripting—including merging logic, XP progression, and interface behavior—was built within Horizon. The game features a long-term progression system designed to take the average player about a month to complete before unlocking rebirth (coming soon), offering a layered and rewarding gameplay loop.

What it does

Merge Kitties lets players merge through 20+ hand-drawn kitties—each with two unlockable accessories, custom beds, and playful personalities. Start with six tower slots and unlock more as you level up. Kitties spawn passively from your carrier, but tapping speeds things up. Use coins and gems to purchase higher-level cats, unlock stylish wallpapers, and earn surprise accessories through the gachapon. Track your progress in the Purr-o-pedia, decorate your board to match your style, and climb the leaderboard as you race to complete your collection. With satisfying sound design, sparkly visuals, and a relaxing gameplay loop, Merge Kitties is built for quick sessions—or cozy, long-haul play.

Challenges we ran into and what we learned

One of the biggest challenges I faced was building a vertical, mobile-only game inside the Horizon Desktop Editor, which doesn’t support portrait orientation. To work around this, I had to construct the entire world rotated 90 degrees—making layout and spatial planning far more complex than usual. Since the game was intended exclusively for mobile, I couldn’t test it in VR to get a sense of spatial flow, which added another layer of difficulty. It was also my first time designing specifically for mobile from the ground up, so I had to rethink everything—from spacing and UI scale to interaction flow, thumb reach, and the pacing of short play sessions. On top of that, we had to ensure the game would function correctly across all screen sizes, which meant building in extra functionality to give every player an optimized experience. Beyond the technical hurdles, I chose to hand-draw every single kitty and accessory to give the game a cohesive and personal visual style. While that added significant time and effort, it was important to me that each piece stayed true to my brand and felt both charming and polished. Balancing custom artwork, mobile UX, and new design limitations all within a one-week timeline pushed me creatively and technically. I also had to work within Horizon’s UI element limits, which was especially challenging for a game that relies heavily on interface interaction. It required careful planning to keep the layout intuitive while still staying under the cap. Despite the pressure, the process helped me grow tremendously as a creator.

Accomplishments that we're proud of

I’m incredibly proud of building Merge Kitties, my first mobile-only game, from concept to release in just about a week. It was a huge creative and technical challenge, but also a meaningful milestone in my growth as a developer. Designing the entire experience for vertical mobile play pushed me to rethink layout, pacing, and usability in a completely new way. I'm especially proud to have created the very first merge game of its kind in Horizon Worlds—an exciting accomplishment that helped expand what's possible on the platform. Every kitty and accessory in the game was hand-drawn in Procreate, and I created custom sound effects to add charm to every interaction. I completed 22 unique animated kitties for launch, each with two interchangeable accessories, which was a major accomplishment within such a short timeframe. The game features a massive progression system that takes nearly a month of regular playtime for the average player to complete. This project deepened my understanding of mobile UX, vertical UI planning, and engagement pacing.

What's next for Kawaii's Merge Kitties

I plan to continue expanding Merge Kitties through regular live updates that introduce seasonal content, new features, and gameplay improvements shaped by community feedback. The game launched with 22 unique kitties: each with two unlockable accessories. I plan to expand that number over time to bring more variety and charm to this cozy game! I’d also love to introduce mini-games to break up the core loop, add interface customization options, and add a rebirth system with milestones and surprises that reward long-term players and keep the experience feeling fresh. Community involvement will remain a key part of development moving forward. I’ll be engaging players through fan art showcases, naming contests, and open suggestion threads in our Discord server to help shape future content. My goal is to create a game that not only evolves with new features and characters, but also with the creativity and passion of the people who play it—building something fun, rewarding, and full of heart, one update at a time.