In 2013, a top executive at Netflix famously announced that the company’s ambition was to “become HBO faster than HBO can become us.” The declaration made headlines at the time for its audacity: Netflix was gunning for the king of premium television. But now it seems Netflix has identified an even bigger rival: the massively popular video game Fortnite. The online shooter accounts for an enormous amount of consumers’ screen time, Netflix said in a shareholder letter Thursday, making it a formidable foe in the global war for Internet users’ attention. “We earn consumer screen time, both mobile and television, away from a very broad set of competitors,” Netflix said in the letter.