World at War: Rounds

GameCall of DutyWorld at War

MapsNacht der UntotenVerrücktShi No NumaDer Riese

Zombies per solo round24 from round 5Nacht, Verrückt, Shi No Numa

Spawn delay3 seconds at round 1floor reached at round 73

Top speedEvery zombie from round 10

Health overflowRound 163

Insta-kill roundsFrom 163 on Nacht and VerrücktAround 208 on Shi No Numa and Der Riese

Highest First Room601, Nacht der Untoten solo

Every World at War First Room world record on ZFRR sits between round 21 and round 46, except two. In solo, Nacht der Untoten has been played to round 601 without opening a single door, and Shi No Numa to round 168. The gap is not a matter of ten times more skill. In solo, past a certain round, every World at War round on these maps is built from the same numbers, so the hundredth round looks like the fiftieth and the five-hundredth like the hundredth. This page explains which numbers stop moving, when, and why it does not happen on the other two maps or in co-op.

The figures below come from the game’s own Zombies script, the _zombiemode.gsc file of the World at War raw files, and from the community references listed at the end. The general picture of the game is in the World at War book.

What a round is made of

At the start of each round the game sets four things: how many zombies the round holds, how long it waits between two spawns, how fast each new zombie moves, and how much health it has. In a solo game on the first three maps, three of the four stop changing early.

Number of zombies

The script starts from 24 and adds 6 for each player beyond the first, scaled up by the round number. With one player there is nothing to add, so the total is 24. Rounds 1 to 4 take a fraction of it: 4, 9, 14 and 19 zombies. From round 5, every solo round holds exactly 24, on round 5 as on round 601.

Spawn delay

3 seconds between two zombies in round 1, then 5% less after every round. It falls below 0.08 seconds at round 72, where the script stops it, and from round 73 it stays at 0.076 seconds for the rest of the game.

Speed

Each new zombie draws a number between the round’s speed value and that value plus 35. Up to 35 it walks, up to 70 it runs, above 70 it sprints. The speed value is 8 times the previous round number, so it is 72 in round 10, and from round 10 every zombie draws above 70. From then on all of them come at the top speed of the map.

Health

The only number that keeps climbing. 150 at round 1, 100 more each round up to 950 at round 9, then 10% more every round, about 5.5 million at round 100.

So from round 73 on, a solo round on Nacht der Untoten is always the same thing: 24 sprinting zombies, released as fast as the script allows. What changes is how hard each of them is to kill, and that is the one number that eventually breaks.

Round 163: the health overflow

The game stores zombie health as a 32-bit integer, which cannot go above 2,147,483,647. Ten percent a round compounds fast:

Round	Zombie health
1	150
10	1,045
30	about 7,000
50	about 47,000
100	about 5.5 million
150	about 650 million
162	about 2.04 billion
163	over the limit

At round 163 the next 10% pushes the value past the ceiling. The number wraps around and comes out negative, and a zombie spawned with that health dies at the first damage it takes, from any weapon or a knife. The community calls these insta-kill rounds, after the power-up they imitate.

It does not stay that way. The next round adds 10% of a negative number, the value wraps back the other way, and zombies are again at close to two billion health. Rounds then alternate: 163, 165, 167 and every other round up to 185 are insta-kill rounds. After that the pattern slips, with pairs like 188 and 189 or gaps like 191 to 194, but it carries on indefinitely, and about one round in two after 163 is an insta-kill round. Black Ops uses the same formula and has the same list.

Past 163, the health of a round no longer depends on how far the game has gone. In health terms, round 600 is no harder than round 200: half the rounds die to a single hit, and the other half sit at the ceiling, the same ceiling every time. With the number of zombies, the spawn delay and the speed already fixed, every number in the round has stopped growing.

Why the dogs move the date

On Nacht der Untoten and Verrückt every round is a zombie round, so health goes up every round and the insta-kill rounds always land on the same numbers. Shi No Numa and Der Riese have Hellhound rounds, every four or five rounds on Shi No Numa, and the zombie health does not go up on a dog round. Each dog round delays the overflow by one round, so the first insta-kill round arrives later, somewhere around round 208, and its exact number changes from game to game with the dog rounds drawn.

That is why the World at War community patch for Plutonium has an Insta Rounds Indicator for Nacht and Verrückt only. The display_instas 1 command shows the next insta-kill rounds on screen, and display_instas_start sets the round where the display begins; a round that is not listed is a normal one. The competitive rules voted in 2025 allow an automatic insta-kill indicator, but only on those two maps, where the list never changes.

Why Nacht and Shi No Numa, and not the other two

Nacht der Untoten

24 zombies a solo round, no dogs, and zombies that cannot hit a player through a window. Insta-kill rounds start on schedule at 163. The four best solo First Rooms, 601, 420, 418 and 361, are all past that point. Leaderboard

Shi No Numa

Also 24 zombies a solo round, with the top speed brought back down after Verrückt. Hellhound rounds come on top, and the overflow is pushed back to around 208. The record, 168, belongs to mr_sudowoodo; it was played entirely before the insta-kill rounds, on rounds where health still climbs. Leaderboard

Verrückt

24 zombies a solo round as well, and insta-kill rounds from 163, but its zombies are the fastest of the four maps and the first to hit through barriers. The First Room is only half of a split starting area, with no perk that works. The solo records are 40 on the Juggernog side and 41 on the Quick Revive side. Leaderboard

Der Riese

The solo total grows here. The script adds the equivalent of half a player, so a solo game has 33 zombies at round 10, 105 at round 30 and 214 at round 46, the record. It also keeps up to 25 zombies on the map, adds Hellhounds, and its last zombie sprints from round 4. Nothing about a Der Riese round stays the same. Leaderboard

Why co-op stays at 40

The 24-zombie rounds only exist because a solo player adds nothing to the formula. Each extra player adds 6 zombies, multiplied by a factor that grows with the square of the round number from round 10. On the maps before Der Riese:

Round	Solo	2 players	3 players	4 players
10	24	42	60	78
20	24	96	168	240
30	24	186	348	510
40	24	312	600	888
100	24	1,824	3,624	5,424

A co-op round never settles. Each one is longer than the last, on top of the rising health, so there is no plateau to hold. The three-player record on Nacht der Untoten, round 40, already meant 600 zombies in its last round. Every co-op First Room record in World at War is at round 40 or below.

The limits of a very long game

Once the rounds stop changing, the limit is no longer the zombies but the player and the machine. A run of several hundred rounds is one continuous game, and the competitive rules for World at War, in the PC version played through Plutonium, deal with what goes wrong over that length.

The 25-day black screen

The community name for a black screen that can end a very long session. The rules allow players to bypass it. The BIOS method is accepted, and since Plutonium revision R5260 the command cl_fix_25day_blackscreen 1 does it. Bypassing it has been allowed since September 18, 2025; it was refused in the 2023 vote.

pause_hard

A Plutonium command that freezes the game to stop some things from crashing it, and lets a co-op team pause without leaving the game. Its use is allowed.

Timers on screen

The community patch adds a game timer and a round timer. Its disable_timers 1 command removes both for the rest of the game, because on-screen elements add to the errors of a long game.

Insta-kill indicator

Allowed on Nacht der Untoten and Verrückt, as above. An automatic “end of spawns” indicator is not.

None of this makes the rounds shorter. From round 5 to round 601, a solo Nacht der Untoten game is 597 rounds of exactly 24 zombies each. On mr_sudowoodo’s 418, the game timer on screen reads 28 hours 41 minutes at round 418.

The solo records

Board	Solo record	Zombies in that round	Insta-kill rounds reached
Nacht der Untoten	601 (Tank Dempsey)	24	Yes, from 163
Shi No Numa	168 (mr_sudowoodo)	24	No, they start around 208
Verrückt, Quick Revive side	41	24	No
Verrückt, Juggernog side	40	24	No
Der Riese	46	214	No

Behind 601 on Nacht der Untoten come Rychka at 420, mr_sudowoodo at 418 and Wonder at 361: four solo First Rooms past round 163, on a map with five windows and two wall weapons.

The World at War book · Nacht der Untoten · Shi No Numa · Verrückt · Der Riese