Re: Bigbroon
I'll reiterate what the GM told me: It isn't against the ToS /right now/. I'm betting they change it eventually.
As for monopolizing a mob, I think it would have to be contested in order for it to be disputed. I'll give an example because I didn't word that well and its late:
A summoner burn party in qufim island would consist of pugils, gigas crabs and bats. An experience party would consist of pufils, gigas, crabs and bats. Therefor, since more than one group is attempting to pull those monsters, the summoners would indeed be monopolizing a zone.
In Korroloka tunnel, or better, the Maze of Shakrami, the pulls consist of leeches, spiders bats and gigas (or leeches, crawlers and bats and I think goblins for the Maze.) No one parties in those zones, and if they do, they move from worm to worm. Since the mobs being pulled by the summoners aren't being claimed by anyone else, ever (just about) its not really a monopoly. Technically.
That said, both opinions are correct, and its arguing semantics to try and prove one way or the other.
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Now someone needs to pull up the definition of "monopoly" and prove me wrong entirely.