Spending studio hours switching back and forth between Stonetop and Freebooters 2e, and right now I’m writing the Freebooters dungeon chapter. If you have the time, I would love suggestions for more things in the following categories. I’m not going to be able to cover everything, but I’m guessing I’ve overlooked some basic things.
Underworld (think Underdarkish)
Origin unknown (most classic dungeons)
GM ADVICE FOR RUNNING DUNGEONS
Situational awareness and constraint (consider the physical space)
Light & Darkness
Traps & Other Secrets
Saving throws & Luck