How does expand (element) work? (Side question: why does the new mock'adyn just have expand water? How is that any good?)
How does Nunk'worn's ability work? And how would you take advantage of that? If Nunk'worn has water 5 and he plays an attack that has water 5 and fire 5 would he do 20 damage?
Those are the ones I can think of off the top of my head.