A game that was confirmed 10 years ago from this very year yet is still not released.
by Edgy child December 8, 2017
A fictional game that many people claim to have heard announced but never came out (a case of the mandela effect)
by wenisses May 12, 2019
The speculated predacessor to Half Life 2: Episode 3.

Though Valve has confirmed that episode three will be the last in the current story arc, they have promised that the Half Life games will continue, most likley through the "episodic medium" they are currently being delivered in.

**Speculation from the next game being the actual anticipated HL3 can be justified by noting that the plot lines of Half Life 1 and 2 are different from one another, so in Valve's admission that the series will not end at Episode 3, it can be inferred that the next title will be HL3**

One thing certain about Half Life 3 is that it will be the continuation of the greatest game ever made, aside from portal, which is tied with half life for that title.
From an interview with Valve on www.stuffwelike.com/stuffwelike /2007/12/12/half-life-3 -world-exclusive/

"TS-SWL: Are there any current plans after Episode 3 to have a Half Life 3?

DL: We haven’t announced anything specific, but Half-Life won’t end at Episode Three – hang on to your crowbars!"
by Glassweaver April 13, 2008
1. A game by Valve yet to be announced.
2. To describe something as highly unlikely and wanted by a lot of people.
1. Half Life 3 on Steam: $33.33
2. Jesus' second coming is officially Half Life 3.
by WhyDoTheseExistNow November 21, 2019
A game that will be realased in REDACTED by Valve Corporation.
Man this half life 2 game is amazing, they should make a sequel, yeah I’m sure half life 3 will be great
by SlimyKlerburt July 26, 2020