>>47746654Just a dungeon? I've only dabbled in Skytemple so I can't say for certain. That being said it seems pretty easy as far as I know, but it depends how deep you want to go.
Ironically, the easy parts are the mechanical things like traps and spawns and such.
Making a tileset for the dungeon requires a little work but it's no harder than you would expect, plus you can just use one that already exists in-game.
Then there's the end of the dungeon which would probably need making a special room for like pic related unless you're basing it off an existing one. You can do a boss fight too but that'll require a little scripting. It may take you a little while to get the ropes on how the coding language works if you're going in green, but from the little bit I've seen and done it doesn't seem like rocket science or anything. There's guides online you can use too.
The weird part is if you want to go for custom music. As far as I'm aware no one thought it was feasible until a little while ago and you need to hex edit to make your song. That being said, there are plenty of tracks you can use in the game for your dungeon, so it's not like it's the end of the world.