I've been thinking about Kaine a lot lately. We didn't really get to know his story.

I've developed a headcanon where he started out really happy and sweet. Like a little baby who's learning how to grow. Only Otto, Arnim Zola, and Hydra beat it out of him.

In the end he was marked as a failed experiment and abandoned in one of Ottos old labs as a security measure. Since he hasn't fed in a while, anyone who goes down there probably wouldn't make it out alive. (Unless they're superpowers of course.)

Bonus: