lose favor with consumers by the end of the 2010s. China's impact in monetization played a key role during this period, which exceeded over 500 million players by the mid-2010s. While the console ban had been lifted, China's government still required that imported hardware be sold through Chinese companies, and requires Chinese operators to manage online games as to uphold the country's laws on censorship and gameplay limitations for minors. Chinese companies that were already publishing games within the country began to make partnerships or other arrangements with foreign firms to help bring their games and hardware into the company through the complex approvals process. Such companies include NetEase and Perfect World, but the largest mover had been Tencent, which made numerous investments into foreign firms over the 2010s, which included full acquisition of Riot Games and partial ownership of Supercell and Epic Games, as well as minority stake in publishers Ubisoft, Activision Blizzard and Paradox Interactive. In exchange, Tencent had helped these companies refine their monetization approaches using their past experience with their own games. Mixed, virtual and augmented reality games Virtual reality (VR) systems for video games had long been seen as a target for VR technology and had been in development as early as the 1990s, but had been hampered by their high cost and impractical for consumer sales. One of the initial attempts, Nintendo's Virtual Boy in 1996, used a monochromatic stereoscopic display to simulate 3D, but the unit was impractical and failed to gain developers, leading it to be a commercial failure for Nintendo. Breakthroughs in consumer-ready VR hardware came in the early 2010s with the development of the Oculus Rift by Palmer Luckey. The Rift was demonstrated at trade shows in 2013, and proved popular enough to lead Facebook to purchase the company and technology for in 2014. Shortly afterward, Valve and HTC announced the HTC Vive, first released in 2015, while Sony released its PlayStation VR in 2016. Valve later developed its own VR hardware line, the Valve Index, released in 2019. While numerous VR games took advantage of VR effectively over "flat-screen" games (those lacking VR capabilities) for immersive experience, VR's "killer app" came by way of Half-Life: Alyx, released by Valve in 2020. Half-Life: Alyx brought several new ideas for integrating first-person shooter gaming into a VR app, and spurred sales of the Index. Augmented reality (AR) games, where the game