Call of Duty WW2 Zombies - Pressure Cooker Trophy / Achievement Guide - In Prologue, survive until wave 20. [Bronze]

The prologue starts automatically when accessing online zombie matches for the first time (it won't trigger in offline mode, has to be online). You can replay it at any time from the online zombie menu.

First you should unlock the Secret Mystery Box. It gives you useful secondary weapons and Jack-in-the-Box bombs which you can use to distract enemies. To unlock the Mystery Box you must shoot the 10 lanterns on this map (4 downstairs, 2 outside the windows downstairs, 4 upstairs).


My Strategy to reach round 20+:

1) At the start of each round, shoot the first zombie that spawns downstairs (it always spawns by the window under the armor shop).

2) Rush upstairs to the armor shop and kill as many zombies as you can (5 in early rounds, 2 in later rounds). You must stand in front of the armor shop. This will lure all zombies towards this side of the map so you can jump down the other side unharmed.

3) Drop down the ledge by the self-revive. Most of the zombies will have gone to the opposite side to the armor shop so you have a relatively clear path when you drop down. However, you should always be shooting your weapons as you drop down so you can kill zombies before the trap you (in case a zombie is about to go upstairs).

4) Now you must "train" the zombies, meaning they all need to be in one line behind you. After dropping down the ledge, head around the big corner (the side of the armor perk), then back upstairs to the armor perk. As you run upstairs, be sure to push towards the wall. This way most zombies won't be able to hit you.

5) Once upstairs, rush back to the ledge by the quick revive (completely ignoring all zombies along the path). From here shoot zombies to fill up your freefire ability. When zombies are closing in on you, repeat steps 3-5 until you have all zombies in one line and the freefire ability ready. Then use freefire with an MG or Assault Rifle and aim for Zombies' heads. Even at round 19 a well timed freefire will wipe out 70% of the round's zombies. Train the remaining zombies again and use the MP-40 or a box weapon to kill them.

*) General Advice: Always have the MP-40 wallbuy and an MG or Assault Rifle from the box equipped. The worst weapons for this are shotguns, pistols, semi-auto rifles or SMGs. You need something that does a lot of headshot damage and has good range. This is important so you can kill as many zombies as possible when using freefire by the ledge upstairs. Don't save on ammo with assault rifles or MGs. They should be your primary pick for kills after round 12+. After round 12 the MP-40 is only good to power up the freefire ability but it doesn't do enough damage to kill enemies quickly. When your box weapon is empty you can draw a new one (leave one zombie alive at end of round and use box until you get an Assault Rifle / MG).

**) General Advice 2: Be sure to draw the Jack-in-the-Box. It's best used after going down and losing the self-revive. Then you can throw a jack to distract zombies and get new armor / self-revive in the meantime.

What can go wrong: After you drop down the ledge by the self-revive it's possible you'll fall onto a zombie below and get trapped. To avoid this, always be shooting when you drop down. This will quickly kill zombies trying to trap you. Even if you do go down you have 3 self-revives in total.

It really comes down to timing and learning the zombie spawns. Everything is scripted, zombies always spawn in the same places / same order each round. The only difference is that they spawn in more quickly in later rounds and can take more hits.