#1 The person(s) who hold the key would be able to destroy or control the AI. Why would the AI want that? The AI was helping Gabriel get the key.
#2 Why/How did the AI choose to work with Gabriel? What made him special?
#1 - The AI doesn't want to destroy the key. It wants to destroy the drive containing its source code. That's why it sank the Sevastopol. The AI probably wants Gabriel to dive down there, use the key and destroy the drive.
#2 - Gabriel has spy skills on par with Ethan's, has self-serving ambitions and love of power that make him easy to manipulate and, most importantly, has a personal history with Ethan.
The AI has already tagged Ethan and his team as one of its primary threats. By choosing Gabriel as its avatar, it gets to mess with Ethan's mind. Luther tipped to this motive and spelled it out for Ethan (and us) which is part of why Luther's so awesome.
Thanks for the reply. That makes sense.
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