As a result, the watermark identifies not only who owns the copyright on a picture, but also who downloaded each copy.

ECONOMIST: In the picture

The first fifty fans affected by this phenomenon to send us a picture holding their special disc 2 will receive a code for a FREE PC copy of Mass Effect Trilogy.

FORBES: BioWare Responds To 'Black Ops 2/Mass Effect 2' Mix-Up With Humor And A Contest

Another tribute attached to a nearby bus stop was a copy of a note written by Hani to his mother, alongside a picture of him as a child.

BBC: Hani Abou El Kheir