What just happened? It’s not often that a gaming company will pay tribute to competitors’ products, but it seems Microsoft is happy to give credit where it’s due. On the 20th anniversary of Xbox, the brand shared a tweet containing an image of the four most iconic consoles ever made—the original Xbox, the PlayStation 2, the GameCube, and Sega Dreamcast—with the caption, “One of gaming’s best eras.”

The official Xbox Twitter account tweeted the message using the #Xbox20 hashtag. The four machines come from what is generally accepted to be the sixth generation of video game consoles, which as anyone who was around at the time can attest to, really was one of the greatest gaming eras.

Going by order of release date, the Sega Dreamcast was first to launch, arriving in Japan in 1998 and the rest of the world in 1999 (except India, which got it in December 2000). Despite being the worst-selling console of the four, those who owned one have fond memories of playing the likes of Shenmue, Jet Set Radio, and Crazy Taxi. Sadly, Sega discontinued the Dreamcast on March 31, 2001.

Next is the PlayStation 2. Released in the year 2000, Sony’s machine went on to become the most popular console of all time, selling 155 million units. More than 3,800 games were released for the PS2, with over 1.5 billion copies sold.

The GameCube also celebrated its 20th birthday this year. The Nintendo 64 successor may have sold 10 million fewer units (21 million in total) than its predecessor, but owners will still remember that fantastic controller and games such as Eternal Darkness, The Legend of Zelda: The Wind Waker, and Resident Evil 4.

Finally, there’s the Xbox. Microsoft’s first foray into this world of video game consoles—the first major one to be produced by an American company since the Atari Jaguar in 1993—was more powerful than its competitors and the first to feature a built-in hard disk. With a games list that included Halo: Combat Evolved, it had a massive launch in the US and went on to sell 24 million units worldwide; more than Sega’s and Nintendo’s machines, but it couldn’t compete with the PS2.

Xbox wasn’t the only one tipping its hat to rival products. PlayStation also congratulated the company on its anniversary.