PortalZ.

Z Chamber 09 Developer Commentary

This was chamber 07 in PortalZ: The 2020 Slice.

Developer commentary may include spoilers; I recommend you finish PortalZ before reading further.


A panel in the chamber under maintenance opens and reveals a behind the scenes area.

This was another area that came from the, “What if in this universe, everything GLaDOS tells you is true?”  For a bit, you would go directly from this room to the turret maze chamber, but I liked the idea of having a bit more going on in the maintenance area in the middle, including a vital apparatus vent delivering turrets as a hint of things to come, and a detached portalable panel observant players can use to skip the first room.


The original entrance to the live fire course.

Before the chamber undergoing maintenance was added, this was actually where you started this chamber.  This and the fake exit at the end are actually the last remaining instances of the original level transition hallway design from before the elevators were added.  I wanted to sneak it in somewhere, and this “alternate testing track” level seemed an appropriate place.


Indicator lights in the maze disappear behind maze walls.

Most players will spot these indicator lights, which lead to the exit, very early on, but not be able to follow them to the button or door.  It is up to the player's spatial reasoning skills to put it all together, though if you peek through the vent, the caged turret intersection becomes a helpful landmark.


The button that opens the door hiding shelves of waiting turrets.

In the maze, I wanted just one dead end that actually kills you.  Though in the end, I was not too mean since you can still escape before the turrets lock onto you.


An intersection in the maze has several caged turrets.

Caged turrets were an element from one of Portal's advanced chambers.  I used a few here just to force the player to think beyond just dropping every turret in sight through a portal.


The cube sits on a button with indicator lights that go through the wall to the left.

If you are paying attention to the indicator lights, you know what will happen when you take the cube off this button, but many players will forget until they try to carry the cube out the way they came in.  It is interesting how, despite most of the maze being portalable, many players will walk through it all while shooting portals under turrets and forget they themselves can walk through portals until they have to.  Meanwhile, others will avoid a slow walk with the cube by portaling straight to the other button.