I only rated this one star because I couldn't rate it lower.
I haven't played any of the previous Gloomspires events, so this would have been my introduction to Leng. But every encounter is designed to be frustrating -- at least those we got to.
As for one particular encounter? SIX creatures for a DM to control is pushing it. More? The DM has enough to do already. That's beyond pushing it. That's just a failure in design. I have to wonder what editor let that through in the first place. Especially with how long these things would take to run in the first place. This is not a four-hour slot game.