It seems like Games with Gold June 2018 lineup has been leaked, at least for one country. A post on the Xbox Wire website for Germany reveals that four new games will be coming to Xbox One and Xbox 360. These games will be available for free at different points in June.
The slate of June 2018’s Games with Gold titles includes Assassin’s Creed Chronicles: Russia for Xbox One, Smite: Gold Bundle for Xbox One, Sonic and All-Stars Racing Transformed for Xbox 360, and Lego Indiana Jones 2: The Adventure Continues for Xbox 360. Irrespective of what the German version of Xbox Wire states, the North American version of Xbox website still has not been updated, so it is not confirmed whether these titles will be a part of Xbox Live subscriptions of countries other than Germany.
According to the official German website, two titles will go live on June 1, and the remaining will go live on June 16. The first title going live will be Assassin’s Creed Chronicles: Russia for Xbox One. Sonic & All Stars Racing Transformed for Xbox One and Xbox 360 is also due to go live on June 1. Smite: Gold Bundle for Xbox One is slated to go live on June 16. Also possibly due on June 16 is Lego Indiana Jones 2: The Adventure Continues for Xbox 360 and Xbox One (backward compatible).