When the Awoken found Riven, it fit in the palm of a hand. It only fed off of Mara’s wishes, no one else’s (except Uldren in the end). So, with Mara alone for food, Riven got huge. Mara must have had a lot of wishes. Freaking hacker already cheated her way into Ascendancy. What else could she have wished for? A hat? An even bigger bow for Sjur to use? Scooby Snacks to make House Wolves do what she wants?

<Death by snu snu>

Riven looks like something out the -blam!-in upside down