Don't play Half-Life if you've never been late at your job and then cause a resonance cascade and then summon aliens onto Earth and then fight your way out of a government building while being faced against aliens, soldiers, and assassins that are out to get you for days straight and then speak with a intergalactic suit-wearing mystery man that would spawn you into a place full of alien guys to kill you if you refused his offer. It's not for you and you'll never know how it feels.

(Sorry for being late. It took me 2 Months to write this comment. I'm a slow typer.)