I'm not sure if something has been altered or if I've just been mistaken about it for a long time, but I've had a few runs recently that all went wrong in the same way.

I previously thought that I had tried helping the NPCs fight the tonberry at the start, but it seemed very tanky and I concluded that you were meant to ignore them and continue down the hall.

However, currently the tonberry dies to the NPCs' attacks in just a few hits, and two more fast-moving tonberries spawn and start chasing after our party, usually killing the person at the back while the tank charges on unaware that they need to pick up these extra enemies.

The first time it happened, I was tanking and I thought I was doing what I'd done before, but it turned out much messier. And then the next two times I was nearer the back of the group and realised what was happening.

So I feel like something is up. Multiple people have it in mind that you can ignore the setpiece "treasure hunters vs the tonberry" and the same bad result happens each time.

Has the first tonberry been weakened, or the treasure hunters perhaps strengthened by adjustments to skill potencies? Are people just pulling more and faster so the trailing tonberries never catch up to the group? Was I just oblivious to them all this time?