"Trust me. You can't do this alone."
Our enemies never rest. If the City is to reclaim its lost worlds, Guardians must band together to stop our foes from completing their objectives.
The City trusts its Guardians to assess the situation - whether a Fallen extraction crew, a Cabal demolition team, a Hive ritual, a mysterious Vex behavior, or something stranger yet - and engage or retreat as you see fit. Every battle won is another victory against the Darkness. But our foes will send their strongest, and they may be too much to overcome alone.
Guardians who band together will survive to tell stories of their triumph. Watch the skies. When the enemy moves, look to the Guardians beside you, comrades and strangers alike.