Sort of like how things are for the way assassins are currently?
Besides, it seems like entwine can work anywhere. It's a powerful skill, and thought maybe it'd be cool if they couldn't entwine EVERYWHERE, and have at least on drawback to it. And no, I don't consider your primary wield being hands (due to entwine) as a drawback.
"Success is not the result of spontaneous combustion; you must set yourself on fire."