Hazard Course: Remastered is a remaster of the Half-Life Hazard Course, a short little training chapter that got you used to standard HL mechanics.
HC:R will feature almost every section from the original HC but with a few new areas inbetween like the ones mentioned in the main description (pistol range, climbing tower, live fire range) and others.
I'm planning to release this around April/May so you won't have long to wait.