The Half-Life Series in Order

Release order is the safest first playthrough: Half-Life (1998) or the Black Mesa remake, then Half-Life 2, then Episode One and Episode Two, which now all live inside the same Half-Life 2 purchase on Steam. Add Opposing Force and Blue Shift after the first game if you want the other two views of the Black Mesa Incident. Half-Life: Alyx is the awkward one. It is a prequel set between Half-Life 1 and Half-Life 2, which is where our chronological list puts it, but its closing scene picks up straight after the end of Episode Two, so if you can play it at all (it needs VR) save it for last.

Half-Life (1998), or Black Mesa if you would rather have the modern remake. They cover the same Black Mesa Incident, so pick one and move on. If you only ever play one game in the series, make it Half-Life 2 (2004): it starts about 20 years later in a new setting and works fine as an entry point, and since November 2024 the Steam version also carries Episode One and Episode Two. Two tempting wrong starts: Half-Life: Alyx assumes you already know Eli and Alyx Vance and spoils the end of Episode Two, and Opposing Force and Blue Shift are built as replays of a story you are supposed to have finished.

There are five mainline Half-Life releases: Half-Life, Half-Life 2, its two Episodes (One and Two), and the VR prequel Half-Life: Alyx, plus the standalone expansions Opposing Force and Blue Shift, the Lost Coast tech demo, and the fan-made remake Black Mesa. Counting the closely tied Portal and Portal 2, this list covers 11 entries. One more exists that is not here: Half-Life: Decay, a two-player co-op expansion Gearbox made for the 2001 PlayStation 2 port, which Valve has never released on PC or Steam.

Yes, if you want the story to finish. Half-Life 2 stops in the middle of the Citadel going up, Episode One (2006) picks up moments later, and Episode Two (2007) is where Gordon and Alyx's arc actually ends, on the cliffhanger the series still sits on. You no longer buy them separately: Valve's 20th Anniversary Update in November 2024 folded both Episodes into Half-Life 2 on Steam, so they start from the same main menu and the game rolls you into the next one when you finish. Lost Coast came along in the same update, tucked into the Extras menu.

No, and most people cannot. Alyx is VR only: it needs a PC VR headset running SteamVR, and Valve has never shipped a flat-screen mode (the NoVR mod that lets you play it on a monitor is a community project, not official). Skipping it costs you nothing going into Half-Life 2 or the Episodes, which came out 13 to 16 years earlier. It matters in the other direction: Alyx spoils the ending of Episode Two and its epilogue reaches past it, so play it after Episode Two rather than at its chronological slot.

Half-Life: Alyx is a prequel set between the original Half-Life and Half-Life 2, roughly five years before Half-Life 2, which puts it about 15 years after the Black Mesa Incident, following a younger Alyx Vance in Combine-occupied City 17. It released last (March 2020) but sits earlier in the chronology, which is how our chronological column orders it. The epilogue is the exception: it jumps forward to the end of Episode Two and changes what happens there, which is why we still suggest playing it last.

Several, yes. Lost Coast is a roughly ten-minute HDR lighting showcase with no story (it is worth loading once for the developer commentary, the first Valve ever recorded). Opposing Force (1999) and Blue Shift (2001) are Gearbox side stories retelling the same disaster as HECU marine Adrian Shephard and security guard Barney Calhoun; both are optional, and Blue Shift is the shortest of the full games at roughly three hours. Portal and Portal 2 are optional too. The one most players actively tell you to skip is Half-Life: Source, a 2004 straight port of the original to the Source engine that mostly adds physics: play the 1998 game or Black Mesa instead. What you should not skip is Episode One and Episode Two, because they are the ending.

On PC, and effectively only on Steam. Steam sells Half-Life, Opposing Force, Blue Shift, Half-Life 2 (with both Episodes included), Half-Life: Alyx, and Black Mesa, which is a separate paid purchase from Crowbar Collective rather than a Valve product. The three GoldSrc games (Half-Life, Opposing Force, Blue Shift) have Mac and Linux builds as well as Windows. Alyx needs a PC VR headset on SteamVR. There is no modern console release of Half-Life 1 or 2: the nearest thing is the Xbox 360 version of The Orange Box, which still runs on Xbox One and Xbox Series X|S through backward compatibility and contains Half-Life 2, both Episodes and Portal. Portal and Portal 2 are also on Nintendo Switch as Portal: Companion Collection (June 2022). This reflects August 2026; storefronts change.

No, and it has not moved forward since 2007. Episode Two ended on a cliffhanger in October 2007 and Valve never made Episode Three. Marc Laidlaw, who wrote the first two games, posted a plot outline of it called Epistle 3 on his own site in August 2017 with the character names changed; it is the closest thing to an ending that exists, though he later called it fanfic and said he regretted publishing it. Half-Life: Alyx (2020) reopened the story rather than closing it. As of August 2026 Valve has still never announced Half-Life 3, no matter how many leaks say otherwise.

Yes: Valve placed Aperture Science and the Portal games in the same universe as Half-Life. Portal overlaps the early Half-Life era, while Portal 2 jumps far into the future, making it the latest point on the shared timeline. They are optional but reward players who want the full picture. The links are references and shared background rather than plot you need, so skipping them leaves no gap in Gordon's story.

Black Mesa is a from-scratch remake of the original Half-Life (1998), built by Crowbar Collective in Valve's Source engine and released in full in March 2020 after years in early access. It tells the same story with modern visuals and a heavily rebuilt Xen section, so it occupies the same slot as Half-Life 1: play one or the other, not both, unless you want the comparison. It is sold separately on Steam and is not included with the original games.