After Baldur's Gate 3 modders made custom maps possible, someone's already working on their own version of Avernus
Not long after Larian released its official modding toolkit for Baldur's Gate 3, it took next to no time for one modder to find out how to unlock a developer mode in it that gives folks to do things like creating custom levels. Now, almost as quickly, the early looks at the first few levels that modders have been working on are starting to pop up, including a version of Avernus.
If you've been living under a rock, these modding tools came as part of BG3's Patch 7 which also included a heap of other stuff, if not everything that some Durge players wanted.
Taking advantage of the possibilities modder Siegfre's 'BG3 Toolkit Unlocked' has, well, unlocked in terms of level editing, a couple of other modders have begun sharing the early work they've been doing in terms of custom maps.