Begins thinking
Valentine's beggining where the wall comes apart.
12 Angry Tests where the test tears itself apart and replaces itself with a new half.
The most cinemanic thing I've ever done in a map is probably in either A Pit Over Toxic Water where GLaDOS wheels in part of a chamber while you are in it to finish building it, or the BTS segment in my map Overhaul.
Designed for Danger ending lift ride.
Aperture Halloween beggining fall.
Nomoney for chambers, exiting the cave and reaching the outside for the first time.
Decay, going through the caves at the end of part 3.
Reconstructing Part 1 by lonewolf, lots of pannel activities and the ending bit.
EDIT: I also forgot the entering of the BTS in Stais Part 2, and the beggining "chase" on the catwalks in Statis Part 3.
I think thats most of the coolest moments I have played through myself, could easily have missed a few though
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