- Added vol 3 info on dungeon doors, secret doors, and traps.
- Random dungeon stocking procedure, with monster tables.
- Hidden (unattended) treasure table, with an associated random trap table.
- Random castle encounters.
- Mostly new artwork.
- A new license, the AELF Open License, which looks like a fixed OGL.
The rest seems identical to the 3rd printing, including errata like the broken turn undead table, missing combat movement and incorrect treasure table rolls. I like the new info and tables - they make WB a more playable game for new refs especially - but I'm disappointed that there was no effort to fix some of the long-standing errata. It's also curious that the new edition comes about 14 years after Matt had said he was leaving WB to the fans. We came together in this forum around 2016/2017 to help Charlie with WB FMAG, which addressed most of the errata and has essentially been the "WB fan edition" since then.
I don't mean for this to be all negative - I think the PDF is worth it for the new tables alone - but I can't see myself using this over FMAG at the table, especially given the errata. It's also worth noting that the PDF is not free, and the POD is pricey at $21 USD, so this might impact adoption (in fairness, the FMAG POD is the same price at DTRPG, but FMAG is still sold at or close to cost on Amazon).