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Portal 2 is a first person puzzle game from Valve. It features a single player and co-op campaign with mind bending puzzles.
SpecsUpdate
Pros
Pro Challenging puzzles that require creative thinking
The game challenges your brain to use portals, cubes and other mechanics in order to solve simple and complex puzzles in interesting ways. Trying to figure out the best placement of entrance and exit portals in order to gain access to (perceived) inaccessible places takes a lot of thought, especially in the later game.
Pro Creates a sense of accomplishment through a high level of teamwork
Co-op multiplayer offers a completely different set of puzzles from the single-player campaign, which keeps things fresh for those that finished the single player campaign. Almost all co-op puzzles require a high level of teamwork, creating a great sense of accomplishment for the players working together.
Pro Huge selection of user-generated content that should appeal to any use-case
The game has more than 60,000 co-op puzzles created by users through the Steam Workshop and through mods. Because it is user-generated content, the quality and size of these puzzles vary widely, including everything from simple, one-off chambers to full-fledged expansions with high-quality stories, voice-overs, and new gameplay elements (for example, Mel). By having such a selection of content, there should be something that appeals to just about anything someone is looking for.
Pro Well implemented tools that improve teamwork
In a game that requires perfect timing and teamwork, Portal 2 features many tools to facilitate said teamwork. One of the most helpful tools is a 3-second countdown timer that players can use to coordinate their actions – e.g., to ensure that you launch a portal or jump at the perfect time. There is also a marker that you can place on certain objects for your teammate to see, as well as a setting that shows your partner's view superimposed on the corner of your screen.