Teenager wanted to scare his friend with gun didn't check to see if gun was loaded

According to a friend, Luke Bryant and Tyler Seaney liked to play a game where where they pointed guns at one another. "The purpose of the game was to scare each other." Last Saturday the 19-year-old boys were playing just such a game in a home in Belfast, Maine.
Tyler scared Luke by shooting him in the leg with an Airsoft gun. So Luke decided to get back at him. According to police records "Luke told detectives he was 'attempting to dry-fire the gun,' and he described dry-firing as pulling the trigger on an unloaded gun, which would still cause the trigger to make an audible clicking sound without the weapon firing."  Unfortunately, Luke failed to check to see if the shotgun he had picked up was unloaded.
Luke pointed the shotgun at the bathroom door, where he knew Tyler was at the time, waiting to scare Tyler when he came out of the bathroom. But because the shotgun was loaded, instead of dry-firing he unintentionally shot Tyler.
Tyler was pronounced dead at the scene. Luke has been arrested and charged with manslaughter.
In the "About Me" section on Luke's My Space Luke writes, "as you can tell from my profile I like guns....."
Ohh shoot.