Some kind of great anyu-like creature that we believe to be called The Tempest is attacking, and doesn't seem to be stopping any time soon. We must come together and defeat this beast!

What I'm seeming to get from this is that we need to fight him together? How is that done? I don't understand. What if you're not strong enough to beat him? My pet's not even strong enough to beat the third challenger from yesterday.

You don't need to be strong enough to beat her. As long as you can do damage, it's fine. :)

Everyone has to work together to chip away at her health until she's defeated. She's WAY too strong for anyone to take down alone. Just hit her hard, go heal when she beats you, and try again.