The PS4 action adventure game Ghost of Tsushima is getting a free update later this month that will add multiplayer content for groups of up to four players, plus some quality-of-life changes to the core single player experience. The release date for the highly-anticipated multiplayer mode, titled Ghost of Tsushima: Legends, was revealed earlier today in a trailer and a detailed breakdown on the official PlayStation blog. [caption id="attachment_920644" align="alignright" width="360"] Image via Sucker Punch Productions[/caption] Legends will allow you to participate in two-player story missions and four-player survival missions, as …