Hacken is a gullible and perhaps stupid hitman, but he makes up for it with loyalty, sheer brawn, and a willingness to go insane when needed. He was a good friend of Tommy Monaghan, Sean Noonan, Pat Noonan, and Ringo Chen.

After becoming involved in a zombie battle at the Gotham Aquarium, Hacken had his zombie-bitten hand cut off in order to prevent infection, and also shot it in order to make sure it wouldn't come after him. Shortly thereafter, he discovered that the bite would not in fact have killed him and turned him into a zombie. He later had his hand replaced with a hook.

Hacken had the misfortune of being the last living member of his friends. He still drank at Noonan's Bar long after his friends' deaths, setting the record straight for anyone who came seeking the truth about Tommy Monaghan and his hitman friends.

As seen in 'Batman and Robin' #27, (March 2014) Hacken sometimes takes a turn behind the bar.