The Draught of Living Death is a very powerful sleeping potion which is mentioned by Professor Snape in the first ever potions class. This potion cannot be made on Pottermore, although numerous ingredients used in its brewing process can be found, suggesting it might be available at a later time.
One of the ingredients in the Draught of Living Death is the Sopophorous Bean. The sixth year students attempt to make the potion during their first lesson with Professor Slughorn.