As Dr. Gordon Freeman, you were last seen exiting City 17 with Alyx Vance as the Citadel erupted amidst a storm of unknown proportions. In Episode Two, you must battle and race against Combine forces as you traverse the White Forest to deliver a crucial information packet stolen from the Citadel to an enclave of fellow resistance scientists.
This is my "The Scent Level Design Postmortem" I'm sure that you'll find it highly valuable. The Scent was a semester based project and it took me 4 months to finish it.
first off expected a simple mapping guide (0.45mb)..
but I have to say I like your thoughts well,
just recommend it to everybody interested in level design :)