Team Fortress Classic Build 874 prototype - Rock2 (full level walkthrough)

TFC Build 874's Rock2 has an alarm system that was removed from the final map. Whenever the player is in the hallway before the key or in the long hallway Cell Block A and the locker room lead to, alarms will go off for several seconds. The alarms play sound and light the area around them red.
Other things of note include the fact that the key is a flag, different announcements from Vox whenever a key is taken or gas is released, a different texture on the doors blocking the HEV Suits, and no text announcement about getting an HEV Suit once someone caps the key.
24:38 Red base alarm 1
37:44 Red base alarm 2
40:14 Blue base alarms
41:46 Taking key and releasing gas
42:35 Red base resupply areas
44:12 Lobby elevators
45:14 Lobby elevators as enemy team
45:32 Blue base Detpack location 1
46:28 Blue base Detpack location 2
47:04 Red base Detpack location 1
47:52 Red base Detpack location 2