Chicken Dung

"Chicken dung!", cursed Jason Jones. "Now I'm trapped in a pile of falling Tetris blocks!"

Then they all turned into CATS! "ALL YOUR BASE!" they said. Also, "Meow!"

Wait! A zero wing! It's wingless! Wingless makes good music. You should listen to it!

Marathon also has good music. The Marathon Man achievement in Halo 3 celebrates the discovery of all hidden terminals, recording the history of a long-dead race - that are actually the ancestors of humanity!

In short: Somewhere in the region of a hundred thousand years ago, this race (known as the Forerunners) ruled the entire galaxy, essentially unopposed. For reasons unclear (but probably of extragalactic origin), a rather predatory alien race arrived in our galaxy, known as the Flood. Despite the Forerunners best efforts and immense technological prowess, they were defeated again and again by the Flood's ability to absorb and transform all biomass. Even destroying the biospheres of a swathe of inhabited worlds as a 'firebreak' failed to stop them; so, forced to the wall, they activated superweapons built on a colossal scale, which wiped out all intelligent life in the galaxy. (It seems likely that they hid some of their own in 'shield worlds' built to resist their super-weapons, and possibly in an extra-galactic colony world of sorts - but there's no proof of this.) Most of the Flood starved; the few survivors went into hibernation of a sort - ironically, on the same superweapons that the Forerunners had created and used to starve them - and waited.

There are many stories to be told of this time - of the Forerunners who strove to save what they could before the superweapons were activated, of those who fought the Flood to try to avoid the superweapons' use, of the AIs that aided and betrayed the Forerunners. But the strangest question is this: Could the Forerunners have been responsible for the Flood's survival after the activation of the super-weapons? One of their AIs, a hundred thousand years later, claimed of one of the super-weapons that "The installation was specifically built to study and contain the Flood. Their survival as a race was dependant upon it." At the time, though, there was strong evidence that he was insane. So one can't say for certain - but the question remains of why they would have been there otherwise. It is known that one of the Forerunner's AIs betrayed them, siding with the Flood at a crucial moment. Could he have worked with them even before that - changing the designs of the super-weapons to create shelters for them?

But wait! It was all a dream!