Tideress will submerge at half health and counterattack you! Come and sit a spell at the enchanting Mystral Lake. Water you waiting for?
The water elementals spawned when the boss is at low HP cannot hit flying Minis. Splitting Harpies from your base can deal with 2 lanes. Whelp Eggs can handle the third lane.
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.