The Battalion
From City of Heroes: Rebirth - Wiki
Overview
The Battalion is an alien force the Rikti Lineage of War battled about 100 years ago. They were mentioned in The Hro'Dtohz file, a clue received in part four of Dreams of Peace and Acts of War arc from Serpent Drummer.
Talking with Prometheus in Ouroboros he will reveal that 'The Coming Storm' is the alien force known as The Battalion.
Apocrypha
Lore AMA Stuff here.