Bleeding Effect

"Prolonged exposure to the Animus caused a 'Bleeding Effect' within Subject Sixteen's genetic structure. The result was a blending of genetic and real-time memory."

―Lucy Stillman's e-mail to Warren Vidic

The bleeding effect was a side effect someone could suffer from prolonged exposure to an Animus, that resulted in an involuntary blending of genetic and real-time memories. Similar in fashion to multiple personalities or delusional disorders, believed by Lucy Stillman to be a naturally occurring bleeding effect, the end result was, in all cases, insanity. In 2012, after being forced to use the Animus by Abstergo Industries, Desmond Miles begun to suffer from the bleeding effect, adopting the Eagle Vision from his ancestor Altaïr Ibn-La'Ahad first, and other skills later still from his ancestor Ezio Auditore da Firenze; although this time willingly. The Assassin, Shaun Hastings also mentions to Desmond during his break from the animus that anyone exposed to the Animus too long won't even need the Animus to see his ancestors memories, although he probably was reffering to subject 16 since it is said he had delusional disorders, Subject 16 himself said in one his Glyphs that he could see his ancestors memories without the animus from time to time.

The bleeding effect was already known to Abstergo Industries even before Desmond's kidnapping, as the test subject before him had been driven mad by it and even commited suicide, but not before he had hacked into the Animus and hidden away a genetic memory from several thousands of years ago.