When I was a child maybe 4 or 5 I used to torture slaters by dropping them in a body of water then fishing them out. My personal tower of london also included sticking pins through the slaters torso, when I was about 13 I took to a host of moths with a pressurized water hose, hunting them down and spraying them until they were dead. That was pure evil. Dunno why...
I had been taught as a child that if an animal was in pain it was better to put it out of it's misery, a pernicious view that I am yet to be able to ween the person who taught it to me away from.
Anyway one day when I was 14 years old, some friends and I were going up to the local school to play basketball. There had been some solid wind the night before and under the hoop lay about 5 or 6 injured chicks that had fallen out of the nest in the tree above. They weren't able to move much and I made a judgement call that there wasn't much hope for them, recalling what I had been taught I decided the best thing was to put them out of their misery, I found a solid stick of wood and took to a couple of them with it, I could only manage two before I realised the task was too grusome and without merit. I think after that moment I decided I never wanted to kill or harm again.
During my life I have killed, stolen many things, engaged in sexual misconduct on several accounts, spent many years lying, creating falsehood, slandering and taken exorbitant amounts of intoxicants.
If I hadn't discovered the Dhamma and turned my life around I would have been on the fast track to Avici. Even now, unless I can gain some sort of security from my practice there's no telling what unwholesome kamma might ripen. The long term kammic trend is mostly downwards, something I hope we shall all manage to escape from.