NVIDIA is continuing their streak of offering PC games to SHIELD owners as Half-Life 2: Episode One is now available on the SHIELD tablet. The game is only available to SHIELD Tablet owners, not SHIELD console owners. This is not surprising as the game requires considerable processing power and only the Tegra K1 inside the SHIELD Tablet can handle that.
It looks like NVIDIA is trying to get more people interested in its Shield portable Android gaming system. While it is a cool device, its really has not caught on all that well. To help gain attention and hopefully sales of the devices it looks like NVIDIA has worked with Valve to bring both Half-Life 2 and Portal to the Shield.