Orb of Darkness
A special orb that can be obtained with a certain chance after defeating the following bosses: Anakim, Lilith, Orfen, Lord Ishka, Queen Ant and Guillotine. Can be compounded with High Priest's Holy Water.
Cannot be spoiled.
The chances are official (x1). On servers with x10, x100 and higher rates, drop and spoil come more often.