Void seed thaumcraft 4
60 120 size electric retracts
Void seeds are created in the Crucible, and used to create Void metal. They can only be created once the thaumaturge has suffered the Eldritch Epiphany. One could wonder what would grow from them, if you could find the proper conditions.
Void seeds are unlocked with the research Eldritch Epiphany which is automatically unlocked when you accumulate enough warp and is the first research in the eldritch tab. Void seeds are used to make Voidmetal. They are also dropped by Crimson Cultists. Contrary to the name, you can't plant them.