The new Nazi zombie map for Call of Duty: World at War is clearly a case of bait and switch. You think you're getting another Nazi zombie map and -- sorry, no Nazis for you! But we do have some Imperial Japanese undead on tap. Perhaps you'd enjoy that?

However, I should warn you that once you've come to the zombie infested swamps of Japan, there's no going back. It may not have the historical realism of the other Nazi zombie maps, but you're not playing Nazi zombies until you're playing Shi No Numa.

Read the review of the latest map pack for Call of Duty: World at War after the jump.

I'm not sure how I feel about fighting Japanese zombies. There's a clear historical precedent for Nazi zombies. They were invented by Peter Cushing. Their underwater combat capability was clearly influenced by the German U-boat strategy for the control of the Atlantic. Nazi zombies have modern relevance as well. They're all the rage in Norway these days. But Japanese zombies? Without women in bikinis to slay them, it just doesn't feel realistic.

It also raises a thorny ethical issue. Is it really a banzai charge if the charger is already dead? The stereotypical Japanese soldier conducted suicidal human-wave infantry attacks, which they do in the latest Nazi zombie map pack, but with more rigor mortis than banzai. Can you be suicidal if you're already dead? The developers at Treyarch dodge this important issue entirely. Maybe next time.

However, the zombie team at Treyarch is getting better at this zombie map thing. The map that shipped with World at War was clearly an afterthought. A proof of concept or an Easter Egg. In the first downloadable map pack, the zombie asylum showed flashes of actual gameplay. And now, in Shi No Numa, there's almost an actual game. In fact, it's going to be almost impossible to go back and play the earlier maps. They just don't hold up any more. Who would have thought that we wouldn't be the ones to defeat Nazi zombies? It actually takes Imperial Japanese zombies.

Shi No Numa, which is Japanese for either "swamp" or "no Nazis for you!", is a wide open map with buildings in the four corners. The gimmick is that you have to keep moving, which is quite a twist from the previous maps. But the "keep moving" in Shi No Numa isn't that crazy Serious Sam style keep moving of Left 4 Dead. Instead, it's more the sense that no place is safe for too long (Killing Floor does this as well).

For instance, every few rounds, hellhounds spawn inside whatever building you're defending. Which isn't very fair, but I guess they're dogs so they don't know enough to play by the rules. Each building has a different soda machine for different perks. Furthermore, the magic crate that gives you randomized weapons will expire and reappear somewhere else. That'll throw you for a loop!

So while the temptation is to stay put and cover the doors and windows, there's going to be a point where you need to move to another building. There's the constant tension of do you stay or do you go now? If you go there will trouble. But if you stay it will be double. It's a constant clash. Esta undecision me molesta.

I don't know the map really well, since it's hard to suss it out when I'm lying down, shooting a pistol, and waiting for one of my useless teammates to revive me (Ha ha, just kidding, guys! Rez plz!). But so far it seems like each of the buildings has its own character, with distinct traps and gimmicks. There's the zombie thresher in one building, which is a must-have for any zombie apocalypse. There's a zip line for quick escape from some buildings. I'm pretty sure the soda machines that give you perks are randomized, but I've been too busy waiting to be revived to take stock of which soft drinks are available where.

The one place where Shi No Numa stumbles is in its attempt to provide Left 4 Dead style characters. There's the honorable Japanese dude. There's the crazy Russian. His name is probably Ivan. There's the hoo-rah American. There's the, uh, fourth dude, which is kind of like that seventh dwarf you can never remember. Doc? They each have their own character model and quips. But the quips are really kind of sad. I don't blame Treyarch for trying so much as I blame Valve for raising the bar too high. But it sure beats Killing Floor's repetitive bloke-isms.

But for the most part, the second map pack for Call of Duty World at War is a flat-out must have when it comes to Nazi zombies. Oh, also, I think there's, like, some multiplayer maps or something in there, too. I think. I should remember to check that at some point.