Those waiting for Half Life 3 are about to get more bad news. There is a possibility that there won’t be a third sequel at all. If the players think back to Half Life 2 Episode 2, it seems that the series has rightfully ended.
The only reason that the Combine invaded Earth was to obtain a teleportation technology to replace the Nihilanth. While the Combine was searching, Breen became high overlord of Earth. This is due to his knowledge of the teleportation technology.
With the constant life-threatening pressure from Combine, Breen was forced to surrender his knowledge to the enemy.
This soon relates to the bomb that was dropped by Eli to save Alyx. Eli is the other individual with the knowledge to teleportation technology. Eli appears to be the missing puzzle and the Combine is desperate to extract his brain. Soon, the worse happened. The Combine got hold of the knowledge and left Earth for imminent doom.
Some 30000 years later, a random robot found the last of the human race hidden deep inside the ground in cryogenic stasis. This continued as an epilogue for Portal.
The bottom line is that there won’t be Half Life 3 at all. It seems that the decade long wait have been for nothing. Bummer.