“Half-Life: Alyx is coming in March, and we are celebrating early by making all games in the Half-Life Collection FREE to play for Steam users, from now until the day it launches!
If you already have Steam installed, you can click the following links to start playing now!
Half-Life 2: Episode One
Half-Life 2: Episode Two
If you don’t have Steam, you can download it here.
Half-Life: Alyx is set before the events of Half-Life 2 and the episodes, but the games share characters and story elements. The Half-Life: Alyx team believes that the best way to enjoy the new game is to play through the old ones, especially Half-Life 2 and the episodes, so we want to make that as easy as possible.”
-> Find the original article here!