The entire planet does not need to go for Arcueid to be defeated. Mass damage is enough. That's my point. Also Arcueid can simply be shut down or knocked without necessarily killing her.
Yeah. Hungry Space is the result of Hungry tongue. It is more hax in that it effects an area all at once and it doesn't have to travel. Hungry tongue does the same thing but it has to strike you. The plus of hungry tongue is that it can be colossal and multiply.