[Webgrave] Which mobs have you found which drop Incantation III?

So with Webgrave, researching Incantation III in the workshop now requires Gnosis IV when previously it was Gnosis II.
No problem; I went to Irongate Castle to summon my old pal the tree stump Grenadier and politely shoot him in the face for a piece of paper.
Sadly, Stumpy's rewards seems to have depreciated in value - he only drops Incantation IIs for me now.
Has anyone found which mobs drop Incantation IIIs with this new update?