As you might have seen from our patch notes of V1.1.0.12738, Arc has a new feature: the autoscan game feature.  Starting with this patch, Arc will automatically populate your library with the following games that have already been installed in your computer:

Phase 1

League of Legends

Marvel Heroes 2015

Aion

Lord of the Rings Online

Penguins! 

Bejeweled

Plants vs. Zombies - Game of the Year

World of Warcraft

Runescape

World of Tanks

The autoscanned games will only appear in your local Arc library and not the cloud library meaning the game must be on the computer you’re currently using for it to appear.  This is only Phase 1 of many more to come. 

You can easily see social news feeds for all of these games on the Arc client just like with all our other games.  You can also choose to play these games through Arc, though they must already be installed in order to do so as Arc does not publish or own any of these games. 

If you have any further questions, please feel free to contact us on our official Arc forums.