Portal 2
Contents
History
(2007-2008) F-STOP
Gameplay
Story
Characters
(December 2008 - 2009) Experimental Era
The Experimental Era follows Valve's failed attempt to transform F-STOP into a sequel to Portal and marks a complete restart of Portal 2's development. This era is named for the variety of gameplay experiments and new features that came about during this stage of development. Some of the new game mechanics that were introduced during this era include gels, lasers, light bridges, jump pads, and excursion funnels.
(2009) Core Hub Era
The Core Hub Era demonstrates Valve's first attempt to create a proper follow-up to Portal after the cancellation of F-STOP. This era is named for its inclusion of a hub world that interconnected the game's six testing courses and allowed the player to progress through the game in a nonlinear manner. Valve later scrapped the hub world in favor of a more linear experience.
Story
The player reactivates GLaDOS and attempts to repair her by retrieving six personality cores. The ending of this iteration of Portal 2 is unknown.
Characters
- GLaDOS (Carcass)
- Mel (early Core Hub Era) / Chell (late Core Hub Era)
- Aquarium Sphere
- Paranoid Sphere (early) / Morgan Freeman Sphere (late)
- Pendleton
- Quint Sphere
(2010) Multi-Core Era
After discarding the nonlinear progression that was being developed during the Core Hub Era, Portal 2 transitioned to a new era known as the Multi-Core Era.
Story
Wheatley is killed off by GLaDOS after her reactivation.
Characters
- GLaDOS
- Wheatley
- Aquarium Sphere
- Morgan Freeman Sphere
(June 2010 - October 2010) E3 Era
Portal 2 was demonstrated at E3 2010.
Story
Portal 2 did not have a proper ending during this era.
Characters
- GLaDOS
- Wheatley
- Chell
(2011) Retail Era
Unused Content
Characters
Aquarium Sphere
The Aquarium Sphere was a personality core that was extremely fixated on aquariums. It was directly inspired by a commercial for the Oregon Coast Aquarium, which became an inside joke among Valve's employees. It was replaced by the Space Core.
A map from the singleplayer campaign in retail Portal 2 suggests that the Aquarium Sphere was in the game until a very late point of development. The map sp_a4_jump_polarity contains an unused logic_relay that is meant to play a sequence that involves a brief appearance of the Aquarium Sphere. Decompiling and editing the map to trigger the logic_relay does not fully restore the sequence because some of the relevant entities have been deleted.
Morgan Freeman Sphere
Paranoid Sphere
The Paranoid Sphere was a personality core that was, as its name suggests, very paranoid. Its location during the Core Hub Era was on a pedestal inside a room that was protected by several turrets. When stood on its pedestal, the Paranoid Sphere would be boastful and brag about defeating intruders who attempted to enter its room. However, when taken off its pedestal by the player, the Paranoid Sphere would become very annoyed and threaten to "go mental".
