one thing most players don’t know about the scanners in half-life 2 is

You can let a scanner serve as a “strider scanner” which occasionally happens not very noticeably in HL2. What this does is, if a strider doesn’t know where you are and is patrolling, and the scanner scans you, suddenly the strider gives a big scary “whoop” and comes running over because the scanner told it where you are.

In final HL2 striders are mostly super scripted, to the point where you wouldn’t think they even had AI (and they need a pretty specific node setup to walk around so they’ll just stand there if you spawn one, too) so this barely gets to happen. I did once make a map where you had to stealth around amoung the rubble avoiding scanners because the strider would come a-runnin but didn’t release it or anything and it’s long gone now. Some of the coolest gameplay not quite delivered by HL2 tho imo.