Ravenous Frenzy (https://www.wowhead.com/spell=323546/ravenous-frenzy) is the Venthyr covenant class ability for Druids. It, by itself, doesn't do anything but should probably be tracked to be shown in the bar for remaining time.

Shard of Silvered Glass (https://www.wowhead.com/spell=335601/shard-of-silvered-glass) increases the duration. (Torghast)

Not supporting this due to the low number of Venthyr Druid players, and, no impact on resources/generation. If someone asks for support later on I may reconsider.