Most everyone on this site probably knows of MarphyBlack but I'm sure some don't so I'm linking his 'Half-Life Fact Files' playlist here. The videos explore specific features that most people aren't aware of or aren't working in the retail release. An example of this is the smell system for the AI which you can still partially experience (NPCs commenting on the stench of bodies) but was intended to be more robust. What makes these videos especially great is how he restores cut features and content to be able to demonstrate them. I'd love a mod that combines all of these cut features but I don't think that'd be possible as some require editing and recompiling maps. youtube.com/playlist?list=PLDmcw…
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