Portal 2 is the long awaited sequel to Portal, made by Valve, the same developer of half-life, Team Fortress 2 and Counter strike. The puzzle game challenges people to use their mind and navigate through the now decrepit Aperture Science facility with only a portal gun in hand to try to escape. Along the way you may find yourself solving test chambers the evil AI GLaDOS has set up, exploring the buried old Aperture Science facility and meeting new characters like Wheatley, an AI personality core that assists you as you escape.
Other than the unique portal mechanic added with the first Portal, all new mechanics have been introduced to enhance the puzzle solving experience. Some of the new mechanics include lasers, laser redirecting cubes, bridges of made of light and gels that give surfaces and objects new properties.
One of the most long awaited feature is the 2 Co-op mode. Named the cooperative testing initiative, you play as 2 robots built by GLaDOS, Atlas and P-body. In the co-op mode, there are all new maps and puzzles to solve, pushing for communication and co-operation between the 2 players. Another new feature is the The Perpetual Testing Initiative, allowing players to make their own puzzles for others to solve.
Atlas on the left, P-body on the right
The game occurs an unspecified amount of time from the original game, but the state of the surroundings show that the time difference is quite sizable. You play as Chell, a portal gun wielding test subject from Aperture science. Woken up by Wheatley, an AI personality core, you try to escape the facility, accidentally reactivating GLaDOS. Eventually you defeat GlaDOS, and Wheatley takes charge of the facility. This drives Wheatley mad with power and knocks you down into the old Aperture facility. While doing so, he also puts GLaDOS into a potato. After exploring the old facility and uncovering the backstory of GLaDOS and the Aperture Science, Chell together with GLaDOS find a way back, put GLaDOS back in charge and send Wheatley to space.
This is a great game with compelling story and interesting characters and the feeling of finally solving a puzzle on your own is a very rewarding one.
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