On the mission Key of the Three Moons I have gotten all parts of the key and killed all the defenders but when I bring Arthas to the gate nothing happens. I have a screenshot but unfortunately don’t know how.
I’m having the same problem
Use the cheat code allyourbasearebelongtous to automatically win the campaign and move on
I ran into the same issue. I noticed one of the blue player dragonhawk riders was still alive guarding the circle of power. This dragonhawk rider was bugged though. I had a bunch of crypt fiends who were unable to attack him, and gave the error “can not attack flying units” when force attacked. Only way I was able to kill it was using Arthas’s Death Coil ability.
Once I killed that unit I was able to trigger the objective complete condition.
All living enemy units around the circle of power must be killed.
All of the units AND all of the towers need to be killed. Not the ones up above overlooking the gate, but the anti air and ground towers on the island outside it all need to die.