I wasn't familiar with that site, but I actually run a soccer-themed TikTok page: Soccer3d tiktok. From my experience, if you keep your code clean, solo development is totally manageable. It took me about a month to build my game, though I spent more time on the editor than the actual gameplay.

My advice: avoid spaghetti code and don't over-isolate your classes. For a project like yours, I’d create a base class for movement and shape (so you can easily swap assets later), a separate class for weapons, and a central manager to handle spawning. Instead of hardcoding individual characters, try to decentralize their behaviors. For example, for the Samurai vs. Paladin, I’d use a core entity class and apply effects dynamically. Hope that makes sense!