Fans have already hope against all hopes that a continuity for the "Half-Life" would still happen. From trolling to leaks, the game's company Valve seems bent on developing the third game. However, it's already been a decade since the last game and, other than the meager information being leaked, there hasn't been any update. For now, fans would have to rely on these leaks for any hope.
One thing fans would need to put into mind is that the original "Half-Life 2" used to have a different approach before the actual content of its final release. Mobipicker was able to cover this earlier, stating that instead of a mundane train sequence, the cut content showed a different opening. At the beginning of the game, the protagonist Gordon Freeman was supposed to follow bell tolls at the distance that would lead to the Borealis, the secret Resistance base in the Arctic.
Spoiler alerts though to those who haven't played the "Half-Life 2" series yet. To those who have played the game, especially "Half-Life 2: Episode 2," it was revealed near the end of the game that the Borealis is a ship that the Resistance discovered along with Dr. Judith Mossman. During development, Valve intended to integrate the "Portal" series into the "Half-Life" lore with the Borealis, adding details that the ship contained technology that the antagonistic Combine would want to get their hands on.
The Borealis was originally intended to have a different role in the cut content of "Half-Life 2" especially back in May 1999 based on earlier source code leaks. It had different versions throughout development, one of which was supposed to be starting point of the protagonist's journey.
In another version of the game, Gordon Freeman would have to hop in a submarine and travel underwater to Kraken Base, another of the cut content. While the final game's Dr. Judith Mossman sported red hair that was tied in a bun, the original cut content featured Dr. Helena Mossman, a blond woman with short hair. The player was supposed to meet Dr. Helena, only to be betrayed. After combatting the doctor and her goonies, destroying the base in the process, Gordon would emerge from the wreckage.
In other news, "Half-Life" will be having its 20th anniversary on 2018 which may prompt the game company to push for the next title, or at least remastered versions of the previous games, according to Neurogadget. There were rumors of a possible new "Half-Life" game when Valve signed a deal with the HTC Company to create the HTC Vive, a new virtual reality (VR) platform. It may be possible that the games in the "Half-Life" series would have VR support.
Although these were only rumors (plus the fact the Borealis was featured in Episode 2), it is still unsure what direction Valve will be taking for the final release... if it gets released at all. Until then, fans would be crossing their fingers.