Destroy, eliminate, annihilate, that's fine. Even evict. The term "genocide" is hard to get in a gaming mood over when it involves racial overtones. For example, we have modern day refugees in my hometown that are genuine victims of genocide- the elimination of their ethnicity- that are still recovering from the savagery against their women, children, confiscation of their property, and so on. Genocide means so much more than just killing people; it's to completely annihilate a race, to stop breeding, torture, and the loss of human rights.
I don't think that's what we're doing here over a game like this. I sure wouldn't play it if it was doing any of these things.
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edit: And I like obliterate.