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To begin the main quest, one must first earn the Ragnarok DG-4.
Beginning on Round 4, the crane will become shockable within afterlife.
A good goal would be to have all 6 gens enabled by then.

After shocking the crane, head to the nearby blue crate; its doors are now open.

At least one player must now stay within the blue crate for the entire duration of the sequence.

Survive the sequence to be rewarded with the DG-4.

Located close to the elevator, one must go into afterlife and enter a secret pathway.

Shock the meter to open the door.

Stand on the pad and plant the DG-4. After a few seconds, they will be automatically picked up.

The player will then be provided with an image hint indicating what step they must do next. There are six possible challenges, which can appear in any order. One can be done per round; failure will require the player to progress to the next round and retry their current challenge.

This step is indicated by this image:

Descend into the labs area and turn on the power.

Eventually, white mist will fill the area and the thief will invade the labs. The player must find the flamethrower and pick it up (if you are fast, you can find the flamethrower before the thief arrives).

One must then find 4 floating blue skulls within the labs area.

Flame each skull until a hitmarker is heard. This must all be done while evading the thief.

If successful, the thief will die and a target symbol will appear on a computer. Quickly interact with it to drain the water pipes.

Take the elevator back up and interact with a second computer.

Wait about 60 seconds for the water to drain, take the elevator back down, and re-enable power.
Note: The step turns off the labs power and both landing pads. If they were previously enabled, don't forget to turn them back on!

A successful step is reflected by this check mark:

A failed step that must be retried is reflected by this:

This step is indicated by this image:

The player must navigate to the Boy of Silence room and enter it.

Navigate to the electrified panel without being caught and interact with it.

This will stun the Boy of Silence. Kill it while it is stunned to complete this step.

This step is indicated by this image:

Three planes will fly over the player and try to kill them. Shoot them down before they leave the airspace in order to complete the step.

This step is indicated by this icon.

Navigate to the Rocket Test site and wait for a rocket test to begin.
As the announcer counts down, begin killing zombies. One of them will drop a meat powerup.

Quickly pick up the meat and press left mouse to toss it under the rocket before you shelter from the test.

Once the test is finished, walk up to the now glowing meat drop to complete the step.

This step is indicated by this icon.

One of the static TV's around the map will now have a red glow to the screen. Here are some of the possible locations:
Labs

Labs

Labs

Labs

Labs

Barrier next to Double Tap

Room Next to Double Tap

Shoot the red TV and wait a few seconds. The screen will briefly flash four different colors.
After this, 4 of the possible TV locations will have the 4 colors on their screens.
Shoot them in the order corresponding to what the first TV flashed.
(Note: Shooting the correct TV will briefly cause its color to turn green.)

This step is indicated by this icon:

Look around the cargo area until you find an engineer zombie:

The player will need to stick close to the engineer as it makes its way towards the pink marker. Take serious caution as getting too close or damaging it will cause it to enrage, failing the step.

The step is completed when the engineer successfully makes it to the marker and teleports away.

Tips:
Dispose of Widow's Wine grenades as they can slow the Engineer down.
Remaining outside of the Engineer's escort radius for too long will cause it to enrage or die.
Use the One Inch Punch to instakill an enraged engineer.
If you have Surge Aid, you can use bubble shields to push the engineer forward.
Keep cool; if you fail the step it can always be retried the following round.

After completing the 6th challenge, progress to the next round.
Make your way down to the Die Rise elevator and ride it underground. Use the key to bring the elevator back up but DO NOT go with it.

Using the nearby switch, go into afterlife and enter through the hidden passage.

Navigate through the hidden area. You will need to find a crack in the ceiling to keep moving forward.

At the top, you will see a Tombstone machine connected to a shockmeter. Shock it.

The pad that was used to begin the quest will now glow green.

Shock the shockmeter which opens the door to the pad. Enter it and plant the Ragnaroks on it.

The player will be automatically teleported to the hidden Tombstone area. They will need to shock bombs to defuse them.

Only one bomb is active at once. Shock all of them to complete this section. Remember the order.
The player is then brought back to cargo. Follow the "target" marker to find an afterlife pickup.

After picking it up, get a few kills until the afterlife pickup is charged.

Activating it brings the player back into the hidden area. All of the bombs will be active and must be shocked in the same order as before.

If successful, the step is completed. Failure will wipe the player that was in afterlife.

After defusing the bombs, a purple orb will spawn on the green pad.

One must shoot the orb, follow it, and shoot it again at its next destination.

Repeat this a few times until it morphs into a cube.



Tip: Try to keep an eye on the orb, it can move underground, into the Labs, or even over to the Rocket Test site.

To charge the cube, get kills next to it. Eventually, it will spawn a shockwave grenade pickup.

Retrieve the grenade. Use it to propel the cube towards the pink objective marker located in the middle of the cargo area.
Pro gamer tip: Shockwave grenades from the box can also propel the cube forward.
After getting the cube to the objective, fill it up with souls one final time.

After filling the cube, it will expand into a much larger, more dangerous cube.

The player will need to find three pink circles on the ground.

Shoot the cube while standing under one to break it open.
Fill the blue circle with souls until a completion sound is heard (Same as soul chest completion).
After filling all three, the nearby afterlife switch will be glowing pink.

After entering afterlife, follow one of the cube's tendrils. There will be a skull at the end of it.

Run through the skull to pick it up. Return to the cube and shock it. The skull will break.
Repeat this entire process until all skulls are exhausted.
Try to get 2 skulls per phase.
After the skulls have been used, the cube will a s c e n d.

The map is now open, zombies will not spawn in for the remainder of the game.

Avoid the space next to the forklift until everyone is ready to continue.

Use this time to set up for the final fight:
Check the Boy of Silence room for a bonus perk objective
Pack-a-punch
Spin the box for better equipment
Set killstreaks
When all players are ready, stand next to the forklift to begin the next step.

Survive in the ship until the pad in the middle turns purple.

Charge the pad by standing on it. Progress is paused if players step off of the pad.

When the pad is charged, pickup the radio and call in the De-Atomizer Strike.

SPOILER ALERT: The rest of this guide will be covering the final fight. Do not continue following the guide if you want to experience it spoiler-free.

Shock the cube when you are ready to begin.

The Master Hand will enter the arena. Players must shoot it until it dies.

After the hand is defeated, shoot the smash ball until it breaks. Activate the final smash.

The cube will split into smaller cubes, fire at the smaller cubes until they become even smaller.
Anytime the cube launches a player, remember that they can boost jump to help regain their footing.
Do this to each cube to complete the phase.
The Crazy Hand will enter the arena. This hand must also be shot until it dies.

Once killed, repeat the same process as before.
The Master Hand and the Crazy Hand will now join forces. Kill them really hard this time.

Throughout the entire fight, pink circles may spawn in. Shoot the cube and stand under a circle to break it open. Just like before, it serves as a soul chest.
Instead of just blue, the broken circles could be colored green, blue, or red.
Green: Two Perks, one Afterlife, one Max Ammo.
Blue: A Summoning Key.
Red: Red Powerups. Avoid this one.
To use the summoning key: Shoot the cube, pick up the key, throw the key at the cube while launched. This will stun the hand/s.

Complete the post-damage phase sequence one last time.
That's it! Congratulations on completing Mission 115! Enjoy the ending sequence.