Hit the 5 switches around the map to activate teleporter in spawn which takes you to the PAP area

1) Collect meteor from PAP area
2) Place meteor in holder near power and then fill it with souls
3) Shoot meteor with Winter's Howl to cool it
4) Throw grenades at 5 generators outside the map
5) Shoot flames on 4 pipes around the map with the Winter's Howl (on rare occasions the fx might not play, it's a bug with the BO3 engine nothing I can do about it unfortunately)
6) Interact with the computer near the DG4 buildable table and note the symbols. Find the corresponding matching monitors around the map to the symbol on the main monitor (4 in total), dogs will constantly spawn during this step and there is a timer
7) Collect Vril device and place in machine (outside near the Gobblegum machine) and then fill it with souls
8) Pick up charged Vril device and then defend the 3 pillars that rise from the ground in various locations once you approach them, if you trigger them and then walk too far away (or if you fail) they will reset and you will need to wait a round to try again, note that they spawn in a fixed order
9) A ball will spawn at the end of the map near the turret traps, shoot it and follow it to the teleporter (do NOT have all switches activated while the ball in is in the teleporter or you WILL glitch out this step - if you want to PAP before teleporting to the boss fight do not move the ball all the way to the teleporter, once it's in there there's no going back)
10) Teleport to the boss arena and fill up the MPD with souls
11) Defeat final boss, on 2nd phase interact with the machine to temporarily disable his shield

Side EEs

Throw Gershes at the 3 'Five' teleporter locations around the map, one gives a free perk, one gives a max ammo and one give points

At round 30 a UFO will spawn and fly over the map

After you complete the main EE you can receive an ice version of the One Inch Punch from the challenge box in the PAP area