Aliens! And with some serious firepower too, with that bird-like thing (some sort of bio-mech?). I wonder how long the war took? With a single unit having that much firepower, multiple units deployed across the globe would mean that it'd be over in less than half a day. Were they here to conquer and assimilate, since it seems humanity was put into captivity for a while (well, at least in some parts)? Or simply extermination? Even more, how did they arrive at Earth? Dimensional rifts? Conventional space travel?
Anyway, these recent revelations just made me reconsider my Half-Life theory, especially since the crucial battle of the resistance movement was spearheaded by a small group (the Fire Maidens). Now, I wonder who their Gordon Freeman was...
