This is a really tough one to answer! There are a lot of really great sessions I’ve had in the past year, but two are complete standouts. Fortunately, I can use one of them for tomorrow’s question, so I’ll link to the other one today.
In November of 2015, I went to Metatopia, which is a game convention in New Jersey unlike any other game convention. It’s basically a con for game designers to go playtest their stuff, and it was amazing. In addition to having a very high concentration of the “game creator community” to talk to and network with, it was also a wonderful opportunity to playtest Threadbare. I ran 2 playtests of the game. The first showed a lot of weak points. The second, where I playtested it with just other game creators, was phenomenal. It helped me troubleshoot the math, the moves, the focus of the game, and how to re-focus it into what I wanted it to be.
In short, if you have played Threadbare, or if you backed the Kickstarter or read the beta rules– you’ve read the game that came out of that session.