DescentBB

In Level 16 of Vignettes (both D1 and D2), the second room contains a door on the ceiling you cannot open manually, but there is a fly-over trigger very close to the door to open it. In the original D1 Vignettes, you can keep flying over this trigger and activating it as many times as you want. However, in D2 Enemy Vignettes, flying over this trigger only activates it once. This means that unless you place a marker in the door, otherwise if you return to this second room of the level and the door closes behind you, you'll be trapped forever (unless the Thief is still roaming around and happens to open it up).

It is not necessary to return to this second room again in the level, but it's perfectly feasible someone would fight the robots beyond the door before actually entering the room, and as is, that strategy alone will potentially result in them being trapped with no way out. So would deciding to return to the room at any later point.

Hopefully Naphtha or someone else (with Naphtha's permission) can upload a hotfix for this potential game-breaking bug. I didn't have a back up save, and had to cold start it.

You're supposed to fly through the door, thus unlocking it.

At any point if I go back into the second room and the door closes again behind me, I'm stuck.

The fly through trigger that opens the door only works once. In D1, it worked repeatedly.

After the first time, you shoot the door.

Try flying over the trigger to open it, then immediately flying back, letting it close, and then try to shoot or bump into it. That's what I did. A lot of people could do this as they try to snipe the enemies in the room beyond rather than flying in.

As for the other part, you're right; once you actually do fly into the room, the door is unlocked from both sides. But there's no guarantee a player will fly into the room rather than retreating to fight.

There must be a bug with your version, because mine unlocks... (You have to fly through it once)

Edit: You have to fly through the door.

I just saw that and edited my post above to show that.

But as I say, not everyone is going to fly through immediately. Some people are likely to think to retreat right away and snipe before flying through. That is what I did, and my punishment? A cold start.

seems like an odd thing for Naptha to change in the trigger department....

It it Matt's change, indeed. I looked up in DLE, original version had a (normal) fly through trigger before the door, that opens it, and Enemy Vignettes version made this trigger one-shot but added another trigger after the door (normal one) So if you don't fly out immediately you are stuck. If you return to the starting room without setting a marker in the door, you are stuck, either. Maybe it is cool that it forces the player to fight in the second big room without camping and sniping from the entrance, but I still consider anything with the triggers that can make the level impossible to complete, to be a bug. It is ok for the secret areas, but not for "normal" path through the level.