Karl didn't pick up a stick until he was well into his teens - 14 to be exact. As a kid he fell in love with the same sport most European kids do, soccer. He loved to play, but he was unfortunately very bad at it, he was taller than most kids in his age group, and disproportionately heavy on his top half. He tried a few positions, but was never good enough to be a starter.
Desperate to find a sport he could excel at, he tried a few winter sports - skiing, biathlon, competitive snow shoe racing, until he found figure skating. He loved gliding across the ice and making smooth transitions, and he was apparently built exceptionally well for lifting a partner. He loved everything about it, the smell of fresh ice in the morning, the feel of cold air rushing through his hair, the fancy costumes, he loved the sport and excelled, getting good enough to compete on the national stage.
On that stage his future was forever changed. He was hands down the best, and he came in as the most highly regarded pair in all of Europe, let alone Germany. Unfortunately skill doesn't mean jack shit in this sport, and he was dealt a cruel blow by the hands of one Russian judge. He finished 4th with his partner, Eegrid. They missed the podium and a chance to compete for Germany.
As any normal 14 year old would do, he threw a fit. He dropped out of pairs, donned a black costume with black makeup and set all of his routines to death metal soundtracks. That particular music does not go well with ice dancing, and he was quickly replaced in competitions.
It was after one of these sorrowful events that he noticed the hockey team warming up on his way out of the rink. It looked marvelous, there were no Russian judges to screw him and the objective was to get the black disk across the line, so the referees had no opportunity to be objectively bad, it was either in or it wasn't, right?

Karl donned his black armor that October, not looking back at his past figure skating. He was a hockey player!