Many games have become classics over the years, whether it’s because of their unique gameplay and compelling stories. One such title, which also happens to be the highest rated on Steam, is currently on sale.

Those who've been following Valve's titles back when the studio was regularly churning out new games shouldn't be surprised to hear that Portal 2 is topping the charts. At the time of writing, it has racked up 386,127 positive reviews and just 4,975 negative ones, for a 97.72 percent positive rating, according to SteamDB. Luckily, if you haven't played it yet, it's on sale for 72 percent off until May 15: you can get it for $2.79.

Portal 2 is a 2011 sequel to its 2007 predecessor. Like the original game, it relies on creative portal creation to progress through its many levels. However, the 2011 title introduced co-op to the adventure. It allowed players to experience the challenge together with their friends, meaning there was twice the fun and twice as many puzzles and levels to solve.

While the game has near-perfect gameplay, especially considering it was released 13 years ago, its strongest point is undoubtedly its intriguing story. However, we won’t go into details and spoil the fun if you haven’t played it yet, because it’s worth experiencing for yourself.