1. Turn on power

2. Find the fuel that can be located near the teleporter and put it in the generator just outside the building you find it in

3. Find a key in a vending machine which is located inside a room locked behind a headshot challenge

4. Now you can open the door in the same room where the box first spawns and grab the crystal inside

5. Outside the teleporter building is a ritual table, place the crystal on that and fill it up with souls

6. Grab it when done and shoot the 4 glowing crystals around that same area, you'll know when its done when a sound cue plays and a the screen shakes

7. In the big warehouse area (where the kill challenge radio is) a gate will be opened next to a giant wooden box with a blue light coming from it. Go in there and turn on a radio in there.

8. Once (or during) the guy has talked, go to the control panel near where the ritual table was and protect it from the zombies. You'll be given a killing time gobblegum when completed.

Note: If you fail protecting it, you can start again next round!

9. If you use the gobblegum, you'll need to find 4 parts. Note: you can only pick up these items when killing time is activated, these part locations are found at...

- In the radio room on a shelf
- Outside the radio room on a table
- On top on the stairs past Stamin up
- On a shelf in the teleporter room

These parts are highlighted red, and you can see them from nearly across the map

Note: If you don't manage to get all parts on the 1st gobblegum, you can interact with the control panel again to start another protection challenge to get another

10. Put these parts on the panel across from a teleporter pad in the radio room, once done you'll need to fix 4 fuse boxes. The first one will be right next to the panel, you can follow the thick cable that comes off it to find the other. Listen out for fizzing too.

11. The teleporter pad is now fixed! And apon entering it will bring you into the boss fight! Be sure to prepare yourself.

Boss fight: Kill the frozen meatballs until you get a sentry power up, this will (of course) activate the sentries in the boss area. Standing near one will charge it up and shoot instantly when finished, make sure the boss is near by when this happens to get a hit on him. Repeat these steps until the boss is defeated

Congratulations! You've completed Overture! Hope this guide was helpful ^v^