I interned at Autodesk over the summer, and was working with 2 other interns (my classmates, co-incidentally; another programmer and an UX designer) to build a narrative driven training experience of Autodesk products.
We were working with InfraWorks, a city planning and engineering software, mostly because it was the closest product Autodesk had that resembled a "strategy game" like experience. One of the goals of our internship was to attempt to build the experience within shipping software, and not on an external engine where the actual product was simply simulated (like a Unity game made to look like it was running inside InfraWorks).
While using Unity would have made our job much easier, building it inside the product would not only help us learn a lot about enterprise-scale software development, but also inform the product team where there product was difficult to use (both externally and in the code base/API) so they can focus future development efforts better.
Here is a small sample of our fork of InfraWorks running what we built: