Tiny Abomination in a Jar (heroic)

Source
This item drops from Professor Putricide in the 25-man heroic version of Icecrown Citadel.

Extra Info
This may be based off of the Episode/Manga Chapter of Full Metal Alchemist: Brotherhood "The Dwarf in the Flask". The original Japanese text for this episode's title is written as "The Little One in the Flask".