All of Araj's Troops will resurrect as a Banshee upon death. Araj doesn't mean to be rude, he just has resting lich face.
For every PvE mission, there is a campaign version and a Heroic version. When you first begin the game, you can only participate in campaign missions. Upon collecting 50 sigils, you will then unlock Heroic missions.
Campaign missions will grant rewards after the first successful clear with ANY family. Heroic missions must be completed with EACH of the 5 different families in order to receive the mission rewards.