Thanks to the author, Dave Johnston, I got to enjoy and finish this MOD. To help out any others playing the game, I threw this walkthrough together since one didn’t exist anywhere on the net, at least that I could find. As he relays in the ‘README’ file, ETC stands for ‘Earthquake Test Centre’. This is somewhat significant as earthquakes and explosions will happen throughout the game, at times opening doors or causing ceilings to fall at critical points.
The game starts with an earthquake shaking the foundations of the building and the room you start in. An alarm goes off and the main steel doors close barring one of the hallways. Exit the door and head down the hallway all the way to the end and another door (talk to the 1st scientist if you want, gives you a little background). Enter the room with another scientist and get the HEV suit and some batteries. Exit again and head for the steel doors. An explosion will open them.
Run through past another door until you see Otis. Pick up the crowbar off the ground to his right and head back to the door (when you grab the crowbar, Otis proudly lets one off). Smash the control next to the door and it’ll open.
Up ahead there’s another explosion and you see Barney cover up. Grab Barney and continue through the gate. There will be a short cutscene with the G-man, then continue. Yet another explosion brings down the ceiling. Go around the boulder and take Barney with you down the elevator. A dead soldier has a gun and in the corner are some goodies in boxes. But careful, a soldier’s on the stairs to the left and a couple more past him at the top. Take him out and grab the grenades on the box on your left. Take out the other 2 (Barney helps) and grab some launch grenade shells from the boxes. In the middle of the stairs is a room with a Turret and some grenades. Be ready for it. Now head to the room to the left at the bottom of the stairs. Inside press the button under number zero (0) that opens the door up top. Be quick because the door only stays open for a short time (couldn’t get Barney to follow me through, though). Careful through the door, a soldier with a shotgun is right there. Continue to next map.
Around the corner is a health. Careful, there’s a Turret at the top left corner of the ceiling and down the stairs are FIVE soldiers. Take them out from the top of the stairs (they’ll run up to the far left corner one at a time). There are two doors at the bottom. To the left of the steel door under the stairs is a health and on the boxes in front are launch grenades. Get more launch grenades from one dead soldier and ammo from the others.
The other door can’t be opened yet.
Head down the hall. Just around the large steel crate are two shotgun soldiers and a health (next to the lamp). Up above the tank is a mini turret and behind it are another shotgun soldier and a door. Up the catwalk are healths and batteries in the boxes. Go through the door and grab the next Barney from under the stairs and take him back to the previous off-white door that wouldn’t open (can’t do anything at the top of the stairs, the door is blocked).
Through the door and past the dead scientist is a Bullsquid. Around the bend you’ll see a scientist get blown up from above. Careful around the corner, there’s a soldier at ground level and two up top on the left that shoot grenades at you. Cowardly Barney takes off back to the door where he let you in when the shooting starts. Once the soldiers are dead, there are shotgun shells and bullets on the boxes. To get through the next door, smash the control panel next to it (bottom part of it). You can go and get Barney from the original door if you haven’t already, he’ll help quite a bit with the next bunch of soldiers (took out 3 of them for me when they ran past me).
Right through the door is a soldier at the end of the hall (Barney gets him), then around the corner to the right are 4 more shotgun soldiers (good ‘ole Barn does a number on some of them if I run out and back so that they attack). To the left up the stairs is a health dispenser and a dead scientist. The door at the end won’t open. Grab ammo and some launch grenades from the soldiers you dispatched. Now you have to leave Barney behind and take a running leap onto the ladder at the back of the elevator past the dead Barney. Make sure you keep either the run key pressed for a bit after jumping to grab onto the ladder or else you’ll fall into the next map and die at the bottom (you can use the crouch key to grab too, but the run key may be easier since you’re already pressing it to run-jump). As you climb down it, we go to the next map.
The next part may be a bit tricky because the ladder ends just above the broken elevator door. You can try to jump to the boulder right in front of the door, but there is a soldier outside the elevator that will shoot once he sees you. You can drop and crouch to the elevator bottom and take some damage then try to shoot or launch a shell at the soldier. He’s behind a barricade so it may not reach. Run up to the barricade (the door to the right in front of it doesn’t open) and the wall behind it on the right will come down partially. Around the corner to the left there are two alien slaves. Past them is a huge stone block on a dead scientist and a Barnacle blocking the way. You can go around but might want to take it out for an easier retreat. At the end of the hall on both sides are barricades. The left one has a soldier and the right has 2. Once they’re dead, you can push the TNT plunger behind the right barricade (elevator doesn’t work). The explosion opens the door by the stone block.
Through the door and around the corner you’ll see a scientist crash through the window and a Zombie come through the door. Kill him before or after he does the scientist in, no difference. Inside the room you can kill the Headcrab through the broken window. The seated Zombie poses no threat. In the room, to the right of the door are 2 batteries. At the end of the hall are two dead soldiers, a health, and one dead Barney to the left. Continue through the next door to the next map.
Map: etc0c (part 1)
Down the hall to the left, right around the corner a Headcrab is poised to pounce. Further left at the dead scientist is a health and to the left of the broken elevator is another hidden Headcrab. Up the stairs is a scientist of no real consequence. At the end of the hall to the far right, past the steam from the ground vent, are three soldiers (one shotgun, 2 machine gun). Past the soldiers to the left is an elevator (go there later). First, take the door on the left, just past the steam. There are 2 grenades in a metal box, BUT be careful, around the corner to the far right is a soldier. Take him out before getting the grenades. The wooden box is empty. To the right again is a soldier behind the fence and across the partial bridge past the fence is another. Take them out and head off to the elevator (can’t cross the bridge yet, but will be able to later). Take the elevator down and exit it down the hall to the next map.
Around the corner and out into the room with the desk are 3 soldiers. 2 on the second level to the right and one on a third level to the left. This is tricky because one of them on the second level is right above you and the one on the third level is above you and further back. Take out the one on the right first. Then you’ll have to sneak in and turn around 180 degrees and try to take out the other two above. Launch grenades are good. Also, in this room is a dead ‘Freeman’ lookalike in an HEV suit and a dead Barney behind the desk with a Magnum.
After the demise of the soldiers, head through the tunnel on your original left. Right away on the right is an Alien Slave. After, on your right again is a pool of toxic waste with 3 Headcrabs. This can be surprising because one is hidden IN the waste and another crosses through it from the far end on the stairs (but as soon as he touches the waste he’s on your side REALLY quickly). Both of these can surprise you, so hang back a bit to take them out. Now, head up the spiral stairs. At the top is an HEV unit, but right on the left is an Alien Slave. Right next to it on the boxes are shotgun shells and bullets.
Down the slope is a health and further on is a Headcrab behind some glass along with 3 shotgun soldiers. The glass may break releasing it, so be wary. Take out the soldiers around the corner and continue. On the right past the soldiers is a ceiling turret behind a fence, so run quickly down the hall and turn left to get away from it where a small explosion will greet you (shouldn’t harm you). Once you turn left to the door you’ll hear a firefight. The soldiers are attacking Headcrabs just beyond the door, so open it and launch a grenade right at them if you have one (will kill both while they’re distracted). Head through the next door and check out the barricaded door on the right. Hmmmm… you can’t get through but those guys look familiar… more Freemans? (You’ll notice that this is the room you see at the end in the final cutscene with the teleporter.)
Head back into the vent (crouch/jump) and turn left and continue through. Around one of the corners is a Headcrab so be ready. Break the grate at the end and turn left outside of it. On the right is the now drained toxic pool. There are two dead scientists and two attacking Alien Slaves where the pool used to be. Go up the stairs and through the tunnel. Careful just outside the tunnel, that ceiling turret you saw behind the fence earlier is RIGHT above you. Blow it away and continue to the right.
In the next room are 2 Houndeyes, 2 Headcrabs and a Barnacle (doesn’t block you, so you can leave it, but get rid of the others). There’s also a health dispenser, a dead soldier and some crates with bullets. Continue up the stairs to another Houndeye. Around the corner is the 2nd level where the 2 soldiers were before. Watch out because when you walk out of the tunnel 3 soldiers will repel down through the ceiling to the level below. Grenades do well here. Continue to the right then left and on your left again is a turret and past it the 3rd level with the 3rd soldier you blew up earlier (has some bullets). Come back down from the and left to the elevator. Behind the pole is another health dispenser. Take the elevator down. At the bottom are 2 Headcrabs and a crate with health. Around the corner are two Bullsquids. Grenades work well with them. Grab the Magnum (bullets) next to dead Barney and continue.
On your right in an alcove will be an Alien Slave. Up ahead is an HEV unit but DON’T use it! It’ll explode injuring you. Coming out of the tunnel is a Barnacle. Careful because right after him a Bullsquid will fall from the floor above and spit as it’s coming down. Best way is to run past the Barnacle (might want to get rid of it first) then back into the tunnel again and try to get squiddy from a distance (or sneak back up on him after he’s fallen down). Further on ahead are 2 Barnacles but you can just sneak past them. Now we’re back to the previous map, but at a different spot (at a ladder that leads up to a grate).
Map: etc0c (part 2)
Climb up and break the grate. At the top, crouch-jump onto the small crate to get to the 2nd small crate. Smash it to get grenades THEN drop down to smash the 1st small crate for a battery (can’t get the grenades otherwise). Press the red button to bring up the bridge (to extend partial bridge you saw earlier).
The door doesn’t open so now you have to head all the way back to the partial bridge that is now complete (still in map etc0c, but you have to backtrack).
Back to The Bridge
Climb down the ladder and go past the Barnacles (back to map etc0c2). Head back to the elevator at the plaque that reads ‘C-623PL’ and ride up.
Go to your left, back to the 2nd level where you killed the 2 soldiers before but watch out because an Alien Slave is waiting.
Continue all the way back through the tunnels past the room with the desk (with dead Barney and dead Freeman) and the Black Mesa sign on the wall (below the 2nd and 3rd levels). Continue right to the main elevator.
Enter the elevator (back to map etc0c) which brings you back up to the door that leads to the bridge.
Open the door and head through and across the bridge. Right across is a health dispenser and a soldier. Only the door at the end opens (other 2 are locked). Through the door is the next map.[/text]
Through the next door are 2 Alien Slaves and a rocket launcher.
Go to the right but DON’T take the elevator on the right (you’ll fall to your death). Take the left door instead that leads to a room with a button that opens the large steel door heading outside. In the room are two dead scientists and some bullets and shotgun shells on the boxes. Press the button and get ready to fight!
Outside behind a barricade are 4 soldiers and a Houndeye. Continue along and in the room with two army vehicles are 3 more Houndeyes, a dead scientist and dead soldier. Kill the ‘dogs’ and watch out because in the corridor on the far right is an Alien Grunt. You might want to sneak in at first to the right and try to launch a grenade or rocket at him while crouching behind the first vehicle. After toasting him, two Alien Slaves will teleport in. Take care of them then head to the left corridor (door on the right doesn’t open). At the end of the corridor is another Alien Grunt and a ladder on the left. I couldn’t seem to reach the ladder to climb it but if you can, there are boxes with health and bullets up top (used NOCLIP cheat to check it out).
Head down the right corridor and around the corner on the right is a hidden Zombie. Another one is crouched next to a soldier, but he won’t do anything if you don’t provoke him. In the men’s room is a scientist you can talk to briefly. The ladies room is inaccessible Through the door at the end are 2 Alien Slaves. Continue on to the elevators. You can try them, but they will explode on the other side and won’t open. At this point a Zombie will break through the security door, so take him out after. Past him is a dead Barney, a crossbow and some arrows. Take the ladder down to the last map.
At the bottom is a scientist you can talk to (in the background you will hear other scientists being attacked). Break the boards barring the door then the door itself then go through. The door to the left won’t open (but you can see a soldier at the far end through the window creeping to the left). The corridor to the left has 2 soldiers and a dead ‘Freeman’ (a dead end to the right). If you crawl to the beginning of the corridor you can snipe both of them with the crossbow (in zoom mode) from the edge of the wall.
Around the corner to the left again are 4 more soldiers (2 come from the back of the far corridor if they hear shooting). If you’re good at stealth you can pick off all 4 with the crossbow if you have enough ammo (peeking around corners). There is also a soldier, 2 dead scientists and a battery in the room on the immediate left (where the door didn’t open into before). Turning left at the end of this corridor takes you to a dead ‘Freeman’, 2 elevators with 2 soldiers, some Magnum ammo on a box and some health on a bench (elevators don’t work).
To the right is a barricaded door with health. Along to the left is a broken window with a Headcrab on a shelf (will leap out at you) and a dead scientist. Further on, you’ll see 3 soldiers. 2 will fire at you while the 3rd fights 2 Zombies in a small room on the left. Once all are vanquished move towards the elevator. CAREFUL here, when you get close to the elevator it will start to come down and when it opens, out will pop 2 assassins. If you time it right, you can launch a grenade and take them both out as the doors open (from a distance of course). NOW, all you have to do is ride the elevator and watch the final short cutscene (Freeman enters the teleport and the game continues in the ‘ETC II’ mod, once you’ve downloaded and installed it, of course)!