Ixia's List
An item list. According to it, you should collect the following materials (10 of each): Medusa's Blood, Marsh Spider Fluids, Nightshade Root, Tyrant's Blood, Corpse Tracker Dung.
Not dropped by monsters.
Cannot be spoiled.
The chances are official (x1). On servers with x10, x100 and higher rates, drop and spoil come more often.