Anomaly Cop

I'm the anomaly cop. I clean up after time travellers.
It all started when my time machine exploded. I spent ten seconds, and ten thousand years, trapped in the has between then and now as they tried to get me back. It didn't quite work, and now there's a bit of my brain smeared across the continuum.
What it means is that I have a perfect snapshot of what the last ten millennia were like the day I jumped. If anyone else goes back in time and causes changes I start getting double vision- their future and my present. It gives me terrible headaches.
So I track them down, travel back to just before they jump, and kill them. It makes the migraine go away.