In the mid-2010s, Bethesda began to experiment with new kinds of games, releasing "Fallout Shelter", its first mobile, free-to-play game in the summer of 2015. A year later, it released a reboot of id Software's "Doom", after several years of development as a failed attempt to produce a sequel to "Doom 3". Later that year, Zen Studios released virtual pinball adaptations of three games that Bethesda released during the decade thus far ("The Elder Scrolls V: Skyrim", "Fallout 4" and the 2016 reboot of "Doom") as the "Bethesda Pinball" collection for its pinball games. Bethesda went on to release two more free-to-play mobile games based on "The Elder Scrolls" series, a card battle game titled ' in 2017 and a first-person role-playing game titled ' in 2019.