The Artifact Defense Event started June 21, 2013 at 5PM (GMT) and ended on June 24 at 5PM (GMT).
This event is focused on special defense missions, which would commonly show up as alert missions during the event. These mission can be identified by their name, Secure the Artifacts. Each of the event's missions rewarded one of three new Artifacts: , , and .
All of these missions are of defense type and require Tenno to survive a variable number of defense waves against any of the three factions.