Originally posted by blackheartz
My question is how exactly will the blade interact with that particular martial art. I guess you do not literally need to draw and sheath the blade on each attack unless the charm explicitly mentions it (like activating the form as a Simple action or maybe Six-Demon Scabbard Binding), but still, there are some weird interactions.
No, you're literally drawing and sheathing it for Stormcaller's purposes every time you attack while int he form.
Can he use the swords initiative to satisfy the requirements for Stormcaller's evocations (eg If he uses Storm Binding: Lightning Cleaves the Heavens can he do it with the sword's initiative)?
If you use Simple Charms to make a decisive attack on the sword's turn (or just make a decisive attack normally on its turn), that attack uses the sword's Initiative.
Can Sleeping Devil, Wake! supplement decisive attacks from the sword as well as the character?
Yes, as can all compatible offensive effects.