It began with The Big Event. The Super Collider went off without a noticeable hitch for the first year. It showed us wonders of the universe we would not know the full impact of for decades in the future. It was a foot note in scientific history, the first time. The second time was a little bigger, and opened up a small fracture in reality, a small pin-hole in space-time that should not have had much of an effect.

Shouldn't.

They came from a different place, with different rules, through that hole. They came as a hive mind, many hives, many minds, and they took over the smaller creatures of our planet, and wrought war on us. Though a hundred of them could die to take down one of us, they had numbers on their size, if not diseases, and poisons, and stings.

The first years were the hardest, and the first half-decade saw the loss of all but a few hundred million humans. What use were our guns? Bombs would damage some, not all. Chemicals would just poison us as well as them. We tried, and though we fought yard, we had to seal ourselves under ground, and for a time, we had to let them take the surface as we fought for control of our own destinies and survival. Underground, we looked for help from the menace that had destroyed our civilizations, and we were running out of hope, when word came from the ruins of Europe. They were going to fire again - maybe they could close the hole, maybe they could find another dimensional crack and we could send some people through. Maybe.

We didn't expect someone to come through the fissure, and offer to help take care of our problem, for a price (to be named at a future date). A deal with the devil, and this man smelled heavily of brimstone, but he offered us a chance to survive.

We said yes.

He sent dinosaurs with god-damn gattling-guns to take care of the problem.