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In this episode the Reptilian Commander is faced with direct, irrefutable evidence that the trans-dimensional aliens really are in control of the spheres - evidence that even convinces the Insectoids they are on the wrong side. Yet he doesn't even question what he is doing, he simply attacks the Insectoids and carries on regardless, threatening death to his own crew if they even question the aliens.

We have seen plenty of 'evil' species before on Enterprise, so there is nothing really wrong or impossible about the Reptilian attitude, but I found the Xindi much more interesting when they were misguided people who genuinely believed they were doing a horrible thing because it was an awful necessity. Now it looks like the Reptilian is trying to destroy Earth basically for kicks, or just because he's been told to do it by the people who he must know, deep down inside, are actually responsible for the destruction of his species. It makes them a lot less interesting.