4 min read

Portal 2 Game Design Review: Part 3

Third part of the Portal 2 Game Design review. These series will dissect the constituent (and sometimes unnoticed) game design elements behind acclaimed Valve's Portal 2.

This game review contains spoilers. Please feel free to come back after having completed the Single Player mode of Portal 2. You'll also better understand all what's commented here after having played the game thoroughly.

Chapters 3-4-5

During these chapters, the game will introduce the player new elements that add complexity to the puzzles, like laser bands that can be used as bridges to walk over pits or as shields against the fireob triggered by robot turrets.

What we need to study here is how the devs will start generating a shift on the gameplay at the end of chapter 4. What’s exactly this shift ?

Now there won’t be more test rooms for a while, as the player will try to escape from GladOS while following Wheatley the robot.  The music will be fast-paced to add as much tension as possible. Instead, the player will be obliged to “walk a lot” through corridors while using portals a few times to move from one near building to another -until now the player has been ‘portalling’ between walls of the same building or room. Now, the distance starts increasing-.

From this point and until the end of chapter 5, the game has even an arcade feeling sometimes (jumping through the ventilation shaft trying not to fall on the abyss, being quick to avoid turrets practicing shooting-match, etc)

Challenges are much easier and direct than on the test rooms,  and involve a simple sabotaging (turrets replacement or cutting the connections of the neurotoxin generator).

As it happened in the first chapters with the introduction of new game elements, devs have been administering small doses again to make sure the player assimilates properly the new mechanics that will be prevalent in next chapters: escaping from huge rooms, ascending through colossal buildings and, again,  ”walking a lot” through corridors and empty rooms.

Here there will be a scripted and easy fight where Wheatley will become evil and GladOS soul enclosed in a potato. Now you and Glados will become partners with the same goal: defeating Wheatley.

Chapter 6

In this chapter, all game mechanics that had being slowly disclosed in the last chapters take new heights, literally. The player will have to transport himself through huge buildings and rooms (that’s why the UI interface warns you about using the Zoom in button to see better where you could place a portal).

Again, there’s a “lot of walking” through corridors and walkways.

There’s a moment when the test rooms “flavor” is reminded to the player again, when he’ll learn two new gameplay mechanics: the repulsion gel (basically an elastic rubber-like material to bounce up in the air) and the use of water to clean the repulsion gel stains.

Following the same rule as before, devs have put a couple of rooms to practice with the repulsion gel so the player is acquainted with it.

Even the game portrays destroyed structures everywhere, it’s an interesting factor to notice that now walls won’t display that aseptic-like white color like in the test rooms.  Being within a factory, the rooms are full of deposits, metallic tubes, dirty mirrors, etc, so figuring out how to escape or where to place a portal won’t be as apparent as before.

These small rooms to test the repulsion gel were a mirage and now we are on the exterior again amongst big structures made of metal and concrete.

Cave Johnson scathing recorded talks (owner of Aperture Science) will join us during our progress, as well as GladOS ones, trying to convince us again to join her going against Wheatley.


In the next and last chapter, we’ll enumerate how game elements are constantly combined from chapter 7 to chapter 9 and give a final word about the overall game experience.

See you in a couple of days!
(you can visit my blog at

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