So I am trying Guldan in Book of heroes, but when I kill all the enemies, I am not able to give any potion, only start over with the same hero. Is that a bug, or do I have to kill the enemies in a very specific order for the puzzle to be solved?.
It is very misleading I think, as it says I can give the potion if I kill all the enemies.
For instance Chieftains of the horde, I end up with my to demons killing the two orange elementals, but that is apparently not the solution to the puzzle, even though I killed all enemies, as I should.
I find it very frustrating and annoying 
Any help would be much appreciated.