Book: The Taken King.
“Without further analysis it is hard to tell what impact, if any, this war on the Taken will have. The Echo destroyed by the Guardian on Phobos will certainly slow their advance. Now that we know of access to the Black Garden in the old tunnels beneath Freehold station, we'll ensure those areas are regularly patrolled and locked down. At the end of the day it is simply too soon to fully appreciate the stain Oryx has left on our system.” - Zavala, after-action report to the Speaker