Judgement is Magical, and all his attacks are weak against mechanical, so start with the dragonling. Drop your decoy, then use Thunderbolt. You want to get as much damage on the pets in the rear as you can so keep thunderbolt on CD. It doesn’t really matter what Judgement does because he isn’t going to be around for long. So spam Breath till he's dead.
Honky-Tonk is mechanical, so we have the Harbinger of Flame ready for him, but don’t switch out just yet. Ride the dragon for as long as you can. He should be able to kill the tonk or be close to it before switching in the Harbinger. Once he's down, just spam Burn until tonk’s dead, save the immolate and conflag combo for the monkey!
Fezwick is a beast, so if you can't finish him off with the Harbinger, bring in the Yeti. Fezwick will start with his stun, so once it resolves send him to Elysium with Call lightning, followed up by ION CANNON! May he rest in pieces ... GG!
Watch the Video below for the oneshot!