You can unlock this by heading over to https://www.trueachievements.com/challenges.aspx
and viewing all currently running Challenges.
As of the updating of this solution, there is currently two Challenges that are active.Current Games With Active Challenges:State of Decay: Year One Survival Edition
(One current Challenge)The Elder Scrolls Online: Tamriel Unlimited
(One current Challenge)
Note: You need to do this in the TrueAchievements app. You do not need to actually buy or download the game and view the challenges there. Simply open the TA app and search for one of the games listed above.
Updated: May 29th, 2020