I'll add a bit more on #1:
Anything you wish, it's here with some species... aggro linked as you mentioned, social within own species, social with other species (except Homins *g*), not caring at all if the world collapses at the feet of the own trough... it's all there.
Some general rules to which there are many exceptions and some tactical prevention means, of course: boss guards are aggro linked, herbies are social and aggros don't care for anything else but what tastes good.
That way your #2 is considered an art by some... there's a lot a puller can do to kill his/her own group
That's all there to be discovered by you beyond Silan. Have fun

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┤Barbarus hic ego sum, quia non intellegor ulli!├
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