I've been doing a lot of combat level prototyping lately, so I thought I'd provide a brief glimpse into my process.
We're going to have a large number of levels that take your party to very different locales, but when designing each one, my approach is similar.
As with most things in our game, the story comes first. To start, I first collect all of the necessary story elements that I may need to convey in a level. Are there any special events that should take place or characters that should be introduced? Where will the combat likely occur given the current status of the party's journey? Sometimes larger story arcs specify dialogue that needs to take place in a level, and other times I'm free to come up with my own chunk of narrative.
Oftentimes, these details will help me define the overall flow of the level and the broad strokes of the composition. For instance, if the party is waylaid at sea by a band of theomechanist pirates, I know that I'll be building an encounter on boats with lots of nice choke points, and there will be some fun banter between the pirates and the party.
Once the story details are understood, I think about any specific gameplay design goals I may have. In the early levels, I usually focus on teaching the player the mechanics of combat and helping them learn tactics that will benefit them in later levels. I also want to make sure that there are plenty of opportunities for the player to exercise their newfound skills.
During this stage, I usually play around a lot with various level layouts, either by drawing on paper or creating quick whitebox levels. We have a snappy editor built in Unity that allows me to build out a tactics level in just a few minutes.
Here are some example levels where I was playing around with height. There are opportunities for the player to exploit ranged attacks from on high, as well as use their push abilities to damage and displace the enemies.
Creating these rough whitebox levels also allows me to pinpoint problem areas before we invest too much time into polishing them. Here's a whitebox level that was fun to play but quite confusing to look at due to the overlapping tiles in the bottom right of this screenshot.
Sometimes I'll do a quick coloring pass over the whitebox level to help communicate a special feel for the location. It's a cheap way to help the player understand a scene before we are able to invest in completing the art for a level. It's surprising how much information you can glean from a few simple colors and shapes.
As with any challenge in game development, these levels are constantly in flux as I receive feedback from players, but you may very well see these levels in the game some day!
Hopefully this little peek into my process was insightful. I'm still learning and adapting, but every level feels like it's better than the last.
Let me know if you have any questions, I'm happy to dig in more if there's interest.