Valve states that gamers can use any visuals they like, and they aren’t required to use images from the game. Once the work is complete, the music video has to be posted to YouTube using the tag “PORTAL2NATIONALEXILE” to mark it for the contest.
The announcement adds that Valve, The National themselves, and the community will be deciding the winner, so the winning video will probably be decided by comment counts and/or video hits. The contest deadline is July 15.
The winner gets a guitar autographed by The National and some Portal 2 merchandise as well. Below is the song on YouTube.
