The ability of a dog to learn from humans has often been linked to its intelligence. Using the dog breeds topic from PetBreeds and data from The Intelligence of Dogs by UBC psychology professor Stanley Coren, we found and ranked the 17 least intelligent dogs by obedience intelligence.
Decades later, in 1945, Dumbledore finally defeated the now-Dark wizard Grindelwald, who had come to possess the Elder Wand. Grindelwald's defeat made Dumbledore the master of the Elder Wand, which remained his until just before his death, when Draco used the Disarming Charm on him.
However, the five of them, with a little help from Harry's remaining stock of Felix Felicis potion, manage to turn the tide of the battle. In Harry Potter and the Deathly Hallows, Neville and Ginny re-activate Dumbledore's army as a means of rebelling against the headmaster, Severus Snape. As there are two other Death Eaters teaching at the school, and the teaching has become a lot darker and more abusive, this is not a complete success.