Board Thread:Episode Discussion/@comment-1599757-20151212162645/@comment-4010415-20151227205907

Phantomlink959 wrote: They confirmed in the recent livestream that the overshield effect was his aura depleting.

^^^^^^

The effect was there to show us that his Aura hit 0.

We didn't see it happen to Weiss because she was in an eruption of lava, so we couldn't see her.

That was pretty much my immediate assumption because it reminds me of when you run out of overshield in Halo, and the RWBY crew have compared Aura to the overshield in Halo.