Talk to Eris Morn

Speak to Eris Morn in the Tower
"Only the oldest tomes mention it, and then only in riddles: a pact so ancient that even the Hive themselves have forgotten it. Yes, I am familiar, Eris. But why do you mention it? Do you believe these fragments of yours are connected?" —Ikora Rey
Added In
The Taken King (2015.09.09)