Necromancy:
Conjuration of the spirits of the dead to magically reveal the future or alter the course of events
Necromancers formed two years after the war. I saw them in their streets, with their strange cloaks and black hoods but I payed them no attention.
I didn't realise that they were a more advanced group than Death Eaters. They looked back on history and learned from the mistakes of others. They valued dark magic, the kind that ran deep within history. They knew more and had bigger plans.
They wanted to control life and death. Kill others and bring those who were once notorious back. They were careful with unforgivable curses, instead opting for Inferi. Their caution made them deadly. They only revealed themselves when their power grew. They brought back Herpo the foul, the inventor of the horcrux and the basilisk. He emerged from the ground, black slime oozing out of him. His deeply wrinkled skin was a moulding grey and his eyes were nothing but a blood red. Everyone ran.
The world went dark after that. Nothing felt right anymore. Then slowly, feelings began to fade. Only fear remained.
Three of the six had used horcruxes to bind themselves to Dementors. That's why they raised Herpo. He knew many things, invented them in fact, that had died along with him. Now reborn, a world of evil was unleashed.
That's what the Quibbler says anyway. The Daily Prophet reports of the Necromancers but leaves a hefty lot out. I suppose they do not wish to scare the everyday wizard and witch.
Liars.