black diamond course
A task that is extremely difficult, or requiring incredible amounts of skill or luck. The term comes from the name of a difficulty rating in downhill skiing.
Tim: How's the new code for the project coming?
Bob: Christ, man, it's a black diamond course. I think this part was coded by monkeys!
Playing quake while drunk is a real black diamond course.
Bob: Christ, man, it's a black diamond course. I think this part was coded by monkeys!
Playing quake while drunk is a real black diamond course.