By now you should have learned to expect the unexpected:
Plot twist! I hope it doesn't look too forced, this was in my mind the whole time. El'Kais was always shown way more sympathetic to the humans than the Eldar, and the decision of annihilating civilian population just as a mean to divert Imperial troops from the scenario was totally unacceptable to him. It was important to me to show the differences between xenos. Where the Eldar see all other species as nothing else than expendable cattle, the Tau try to not sacrifice them; not because they have higher morals, but just as a philosophical racial issue for survival.
Eldar see how they've lost their empire, their true identity, how everything they once had did vanish in front of them, and feel threatened by mankind and any other race. Though every Craftworld will have a different approach to the issue, they all see men (and others) as intruders, as lesser races not worth of being compared to them, so they all are eventually expendable.
On the other hand, Tau are at the early stages of their expansion, they cannot afford mass genocide as a valid way of usual relationship with other races. Their first try is always assimilation (and then genocide if that fails), it's the quickest way of building an empire given their resources and means. They don't share that idea of racial purity which inspires all Eldar thoughts, but they rather embrace the concept of conquest and brainwashing, so they can use any people and resources they find. Not that they consider other races as equals, as they cannot make any real progress in Tau society (everyone has a place, but a determined place). In fact all that stuff about the so-called Greater Good is pure bullshit, the way of mass control within the Tau society and towards all the conquered races.
So well, I might have been wrong when I said that Tau don't see humans et al as mere cattle, hmm...
But I digress, as usual. I was talking about Brent on the run and suddenly El'Kais helping him. Apparently Ellinderelion foresaw a number of possible futures and, by provoking this to happen, settled a scheme of events as the least grievious path to his people. That's kind of Machiavellan, but it's exactly the kind of thing you could expect of him. He still will have to prove his ways, but at some future point I was (eventually) going to show the whole course of events and why expelling Brent and making an enemy of his former allies the Tau was to be beneficial to his cause. For the moment just enjoy the unexpected tension!
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