A hallucinogenic substance, it is sold by the Cartel, and is a lot safer to use than their other product, Rot, which is said to slowly bring about insanity. It is very similar to wheat in appearance, so is much easier to smuggle than it's counterpart.
Weeeeed was first sold in the city of Montecristo, a city controlled by King Mystiko, who later merged his faction and the city into Evorga, another faction known for it's stance on substances sold by the Cartel.
Though not proclaimed illegal in many factions, it's use is often frowned upon, and it is hard to purchase on the open markets. Due to this, the substance can only normally be purchased from dealers of the Cartel, much like how Rot is purchased.