On April 18, 2011, Portal 2 was released for the PC, Xbox 360, and PS3. The original Portal was released on the Orange Box, a package of great Valve games together in one place. However, while Portal was more of a tech demo than a full-fledged experience, Portal 2 came with more depth in its story that is still remembered to this day. Meanwhile, its co-op experience goes down as an all-time favorite for many, and those fans are celebrating the game's 10th birthday.

Portal 2 is a game that sticks with those who play it. Because of the amazing puzzle design, gripping story, and brilliant co-op, the game is one that is not easily forgotten. Now, 10 years later, fans are taking to Twitter to remember one of the classic games of its generation.

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The Game Awards Twitter page was one of the first to congratulate Portal 2 for its big day; with some birthday cake of course. Portal is home to one of the earliest big Internet memes, "The Cake was a Lie," and many are referencing that with artwork, cake emojis, and more.

Even games outside of Portal have been making cake references, such as Assassin's Creed Valhalla making a Portal cake joke just last year. Portal 2 being 10 years old is hard to believe considering how present it still is in modern pop culture, so it feels like the game deserves to enjoy a nice slice of birthday cake.

Even though 2011 was one of the best years in gaming history generally, Portal 2 sticks out as one of the big reasons why. The game has a score of 95 on Metacritic, which makes the game one of the highest-rated games ever on the site. Based on the Twitter responses from fans, it seems that players still remember the game very fondly.

From the game's frantic opening to its breathtaking finish, Portal 2 is filled with twists and turns. One of the things that makes it so special is that it feels like an evolving game, as Wheatley's navigation in the early stages of the game is very different from the 1950s-era Cave Johnson recordings (voiced by actor J. K. Simmons) during the second act of the game. There is a reason that many remember Portal 2 as one of the best games of 2011.

Along with this celebration, many are also hoping that Valve will eventually make Portal 3. Time will tell if that becomes a reality, but for now - 10 years after its release - many are simply happy about the joy that Portal 2 gave them.

Portal 2 is available now on PC, PlayStation 3, and Xbox 360.

MORE: The Case For Valve To Bring Back The Portal Series