Why the Profound Darkness Truly is Evil
I've heard a lot of people say, "Well, we don't really know that the Profound Darkness was evil. Maybe it was just an innocent victim of the Great Light's cruelty, or something like that." To that I can say only one thing -- PLEASE. The Profound Darkness is evil. (And that fact does not necessarily have anything to do with the goodness or evilness of the Great Light, by the way.)
Consider: a being which is actually good would not destroy entire planets and slaughter countless innocent people for its own personal benefit. Most morally-neutral beings probably would not do so, either, due to the incredible feelings of guilt and remorse that might threaten to consume them. So, even if the Profound Darkness was treated in an outrageously cruel and unjust way by the Great Light, if it really was good, it would not endeavor century after century to eliminate as many innocent people as possible. If the Profound Darkness was actually good, it would resign itself to its fate long before it would begin massacring innocent people who cannot help the fact that they just happen to occupy the Algo system. Destroying the innocent people for its own personal benefit would be evil, get it? There's no room to wonder about the goodness or evil-ness of a being when every last one of its actions is clearly a demonstration of incredible evil!
Also, consider the fact that Dark Force, which is a manifestation of the will of the Profound Darkness, feeds off of negative emotions such as pain, anger, and sorrow. How can that possibly stem from anything that is good? Saying goodness could produce Dark Force is like saying you could get ground beef out of an apple.
As for the Great Light, I am not saying that it is necessarily a totally good being, although I personally believe it is (since it is the counterpart of the totally evil Profound Darkness). But when one simply looks at the actions that the Profound Darkness chose to take again and again, it cannot be denied that the Profound Darkness was an evil, wicked, cruel, deceitful, and wholly self-serving demonic being. There is nothing good to be found in that.
If one is simply willing to admit that good and evil do exist, one cannot deny that, while we cannot necessarily determine the level of goodness of the Great Light, we cannot fail to see the fact that the Profound Darkness was purely evil.
I would like to close with a word in the Great Light's defense. Many people have said, "How good can the Great Light really be when it left all those poor Algoians to be killed by Dark Force?" My question to those people is, "What the heck else was the Great Light supposed to do?" The Great Light and Profound Darkness must have thought that defeating each other was very important, or else they would not have fought like they did. So, if the Great Light had been capable of defeating the Profound Darkness any more completely than it did, don't you think it would have? If the Great Light had been capable of doing any more damage to the Profound Darkness, don't you think it would have stuck around to do that damage? Of course! It wouldn't make sense to do otherwise!
So, having done every last thing it can do to keep the Profound Darkness in check, and having absolutely not one more thing it can do, why shouldn't the Great Light go off to attend to other matters? What would have been the point of sticking around in Algo? Answer: there would have been no point.
I'm not sure why people are so eager to vilify the Great Light while they canonize the Profound Darkness. Maybe it's sometimes a hostility towards any kind of objective morality, and maybe sometimes it's just a failure to remember what facts were established in-game, and maybe sometimes it's any number or combination of possibilities. Regardless, the facts of the game, when combined with basic reasoning, should make it clear to anyone and everyone that, yes, the Profound Darkness was evil. Profoundly so.