Lilith

Lilith is a boss added by Witchery. To summon her, complete the Creatures of the Night ritual to summon Elle. When Elle is lead to a large Lava lake in The Nether she will transform into Lilith. Lilith will fire fireballs at the player. When defeated Lilith shrinks and can be given:
 * a Glass Goblet to fill with her blood, allowing the player to become a vampire.
 * a Poppy to promote a level 6 vampire player to level 7.
 * a tool, weapon, or armor piece to bestow a random enchantment on it.

Once one of the aforementioned items are given to Lilith she disappears afterward.