Though it may be a difficult pill to swallow, the original Xbox is now a vintage artifact. For context, the Nintendo Entertainment System (NES) was just over 15 years old when Microsoft’s console first hit store shelves and that felt positively ancient at the time. Yet the Xbox is now almost old enough to legally buy alcohol in the U.S..

The gaming system launched on Thursday, November 15 in 2001 and managed to shift 1.5 million units before that calendar year ended (550,000 of which were sold in the initial week). Since Atari got out of the market in 1993, it was also the first American-made console to pose a real threat to the Japanese titans of Sony and Nintendo.

The rest is gaming history and, three generations later, the brand is still going strong. In particular, the Xbox 360 was a massive hit, ending up as the ninth bestselling console of all-time, and that is including handheld platforms.

To celebrate this enduring success, Microsoft is hosting a special 20th anniversary celebration livestream today, which will reflect on the past couple of decades and the blockbuster titles that defined them.

Here’s everything you need to know—including the start time and how to watch live.

How and when to watch the ‘Xbox Anniversary Celebration’

“The Xbox Anniversary” celebration will be broadcast on the official Xbox YouTube, Twitch and Facebook channels. To watch it live, you will need to tune in at 1 p.m. ET on Monday, November 15.

Of course, a recording of the entire stream will be hosted on those channels for posterity’s sake, so you can always catch up on it later if you miss that timeslot.

What is the ‘Xbox Anniversary Celebration’?

Microsoft has stressed that this is a retrospective livestream, celebrating the past 20 years, rather than a look at what’s to come in the future.

As such, those who are hoping for new game reveals might want to temper their expectations a little. This is not going to be like a Nintendo Direct or PlayStation Showcase, where huge announcements are made every other minute. Instead, it is probably going to resemble a series of mini-documentaries that highlight the impact of certain landmark releases.

Speaking of which, it is assumed that the Halo series will be featured prominently in this broadcast. The original game debuted simultaneously with the Xbox (meaning that it turns 20 today as well) and it has been identified as a key “system seller.”

Not only that, but its sixth mainline entry, Halo Infinite, is due to be released in just a few weeks, so it makes sense to get everybody feeling nostalgic about the franchise in advance.

A theory has been gaining traction online that Halo Infinite’s multiplayer component might be dropping 23 days early at the end of the livestream. This would certainly be an unprecedented move, as games are much more likely to miss their projected release dates than they are to overtake them (as Halo Infinite itself has demonstrated once before).That being said, it would undeniably be a great bombshell to end the presentation on.

Otherwise, we might get a few announcements about expansions for the Xbox backwards compatibility library, with some classic titles getting rereleased or even put on the Game Pass service.