Avenger wrote:
Some easier than others, in no particular order:
What temperature is the interior of the Black Mesa Research Facility maintained at?
Where is the only place in HL1 that Barney Calhoun appears (the character, not his stock model)? What about Eli Vance?
In the "Power Up" chapter, after turning on the power you use the train to crash through the barricade in the tunnel. However, if you were to noclip through this barricade without playing through any of the chapter, you would find several detpacks, tripmines, and possibly other ammo behind the barricade. Why is this ammo here? There is a valid answer to this question.
What is inside the Gman's briefcase?
Which teleport in the lambda core will kill you if you jump into it? What is the correct order to jump through them?
What is Gordon Freeman's disaster response priority? Who is his administrative sponsor?
In the Anomalous Materials chapter, there are some rotating billboards near the elevator to the test lab level. What does the fine print on the billboards say?
What game-over text do you get if you jump off or drive the dune buggy off the cliff in Highway 17?
Which locations from Half-Life are revisited in Opposing Force?
What is Dog's eye made of?
The only place Gordon sees Barney Calhoun is when he's in the tram in ch.1 and passes by the security guard that is out side the door.
Eli Vance is seen with that other guy in Unforseen Consequences and tells you to get help.
Dog's eye is made of a scanner.
That's all I know of right now as I've only played a very very small bit of HL1 and all of HL2 and EPs 1 & 2. I know what you're talking about in regards to the game over text in Highway 17 but I forgot it.
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