The Hazardous-Course 2 is a spoof of the original "Hazard-Course" from Half-Life, which resembles the first player training levels. In contrary to this, the Hazardous-Course, as it's name let's suggest, is much more dangerous.
Although it's a mod for a first person shooter, the player can only wield a weapon at the designated target range. So it plays more like an adventure.
The difficulty is quite challenging, but the rewards are accordingly. The Basic Training is peppered with hidden Secrets, which reveal tools, shortcuts, control rooms, and other features, to ease almost all challenges.
There are two Secret Levels and one Bonus Level to discover, and to complete to access the final part of the Hazardous-Course.
Help can be found on the page in form of a FAQ and a complete walkthrough. Unfortunately these are all in german. But to be translated soon.
But be aware, that these helps may spoil some surprising Easter eggs, insider gags, and a lot of the actual game play of the HC2!