Pretty easy fight for you outside of maybe some nasty crits on the Druids part. Control the Paladin, watch out for Hand of Sacrifice on the Druid and keep your distance. You're going to want to minimize the initial damage as much as possible via Deep Freeze after pounce and/or trinketing the maim and Death Coiling the druid off you. Don't be conservative with your portals, and dump your damage into the Druid. Feral Druids don't have much caster defense abilities, so landing the kill should not prove to be too difficult.

Mage PoV:

Just stay close to your Warlock so you are able to get a Nova/Deep Freeze off on the Druid right away. He will most likely trinket the Deep Freeze so just be ready to freeze him again with your pet nova. It's a Druid, so he will be constantly shifting out of your novas. You will want to blow Cold Snap pretty early in the fight to keep up on novas. Spellstealing Freedom and Sacrifice as always.