Thought I'd drop in and give this a review. I like how both the prologue and first chapter are quick and to the point. I also like Teridax's speech to the Mahri. I wonder what he has planned for them.
I did notice a few grammar errors. Some of them are that the names of some of the beings are not capitalized. Names like 'Rahi,' Rahkshi,' and 'Toa' always need to be capitalized.
There are also a couple sentences that I think could be worded better. They are:
:Tahu’s current “base”--if it could even be called a base anymore, Teridax ruled the entire universe--was Metru Nui.
Since the previous sentence already states that Teridaz rules the universe, I don't think it needs to be repeated in this sentence. Thus, I think it should be omitted.
“We can’t give up. Not now. We fought. We fought as Matoran, Toa Inika, and Toa Mahri. We cannot give up now, for the universe we once really lived in.”
I think the bolded part could be omitted or rephrased. As is, it sounds and looks a little weird. Maybe he could say 'We have fought him for over as long as I can remember' or 'We have fought against him all this time.'
But anyway, I liked you prologue and first chapter. Keep up the good work!