>>111340766Well, the theory I liked had it that the villain is a sole survivor of a planet besieged and harvested by the diamonds, but this happened 4 millennia ago. After getting over the initial shock/despair of the fact that all his loved ones and people were dead, he drifts through the universe learning more about what happened to his planet the Gem empire and the fact that what happened was a pretty common occurrence. After learning this he gets direction in life, using and modifying discarded Homeworld tech to support his new goal of making sure the diamond authority pays for what they've done and to make sure they are never able to do it again.
Now personality wise he is surprisingly amiable, he shows a high level of respect to the other character even if they're in his way. A trait that often throws people off but that isn't his intention but a side effect he is perfectly willing t take advantage of. Despite being heavily cybernetically enhanced he neither his robotic or biological can stand a fair fight with most Gems, so he never gets into one. Heavily relying on cunning and smart use of his equipment to get out of dodge while advancing his final goal.
Now I liked this theory for a few reasons. I gave you the simple version from memory but the full thing gave a reason as to why Homeworld has such a strong army, some Planets have a populace with tech advance enough to give them issues so they have to bring the army in to drop the hammer. I find the concept of the villain interesting in this setting, he has both a strong logical and emotional reasons for wanting the Diamonds dead both of which are hard to argue against, his nature also means that he has a strong contrast against the other villains. Rather than a powerful force who looks down on their enemies, this guy is an underdog who respects and in some way even looks up to them.