I'm taking my time to design Arborshire because it's very ambitious and complicated, and I have the experience to do it well. That means I can finally "justify" developing some of my own external tools just to help develop the main game! (I've always wanted to make something like this but the time investment didn't make sense).

What I've started working on is a tool for dungeon design (works for Metroidvanias as well). The goal is just to visualize a dungeon level, and allow me to quickly iterate. It does what graph paper does already, but digital. I want to support features including locks/keys, labels, stamps, and multiple states. I also want to include some useful algorithms, like a dungeon solver and a soft-lock checker.

Additionally, I posted a devlog video showing this tool and talking more about what I plan:

I am developing this tool primarily for my own use. It will be used to prototype handcrafted dungeons to test ideas for Arborshire's grand procgen dungeon. However, I will release it publicly as well. So, if you might use a tool like this yourself, let me know what you'd like to see. I'm prioritizing my own use case but if there is interest I can expand the scope.

P.S. I'll probably name it "Sepulcher" which is one of my favorite words. It just means a type of tomb/crypt which seems like something a Zelda dungeon could be called.