Destiny 2's big new update is in many ways a celebration of developer Bungie's past, and that includes its work on Halo. Among the new weapons that have been added are a variety of Halo-inspired ones, and while these can generally be obtained from the new six-player Dares of Eternity event, another will require some more effort. That gun is Forerunner, an Exotic sidearm that is quite clearly based on the original magnum from Halo. Here's how to get started on the Magnum Opus quest--we'll be...