The First Room

On ZFRR, the First Room of Nacht der Untoten is the starting room: the large ground-floor room of the bunker where the players spawn. In World at War, every game starts there with 500 points, an M1911, the knife and two Stielhandgranate stick grenades.
Two ways lead out of the room, and both stay closed in a First Room game: the door marked “Help”, to the right of the spawn, for 1000 points, which opens onto the Help room and the Mystery Box, and the sofa barricade on the staircase, also 1000, which leads to the upper floor. The zombies come in through five boarded windows. Each board put back pays 10 points, up to a limit per round.

Kar98k
200 points, a bolt-action rifle drawn in chalk on a wall of the room, the cheapest wall weapon of the map.

M1A1 Carbine
600 points, a semi-automatic rifle with a 15-round magazine. Its buy prompt calls it the “M1 Carbine”.
Those are the only two wall weapons of the room. Everything else, the Mystery Box included, is behind the Help door or up the stairs. In World at War the room is even barer than in the later versions:
Windows that hold
A zombie tears the boards off a window but cannot hit a player through it: it has to climb in first. From Verrückt on, and in the Black Ops remaster of this map, the zombies hit through the barriers.
No perk at all
Nacht der Untoten has no Perk-a-Cola in World at War, so every run is played on 100 health, two hits and down. Mule Kick, which stands in the starting room of the later versions, only came with a Black Ops update.
Nothing else
No power switch, no trap, no Pack-a-Punch, no special round and no Carpenter power-up.
What does drop is four power-ups, Insta-Kill, Double Points, Max Ammo and Nuke, and in World at War the two timed ones count down in plain text:

Insta-Kill
A glowing skull dropped by a zombie. For 30 seconds, every zombie dies in one hit.

Text timers
The remaining seconds of Insta-Kill and Double Points are written at the bottom of the screen. From Black Ops on, an icon replaces them.
In solo, every round from round 5 holds exactly 24 zombies, the spawn delay hits its floor at round 73 and the health of the zombies overflows at round 163, which brings the insta-kill rounds. That is why the solo board of this map goes past round 600, far beyond every other World at War First Room. The whole mechanism is explained in World at War: Rounds.
The Nacht der Untoten leaderboard keeps a board for each team size, from solo to four players. World at War has no First Room rules of its own at B2: its World at War rules apply, on top of the First Room itself. The ones that matter here:
Doors closed
No door may be opened, the Help door and the sofa barricade on the stairs included.
Full rounds
Every round is played in full, and glitches and exploits are not allowed.
Regular difficulty
The campaign difficulty must be set to Regular.
Platforms
On PC, only Plutonium with the verified community patch, its anticheat output always visible; the Steam or disc version is not accepted. Xbox 360, Xbox One, Xbox Series and PlayStation 3 are accepted.
Indicators
An automatic insta-kill round indicator is allowed on Nacht der Untoten and Verrückt only. An end-of-spawns indicator, a trap timer or a zombie counter is not.
Old School ranking
Solo and two-player runs count in the Old School ranking, converted to the equivalent round on the Black Ops board of the map: past round 73 the endless solo rounds are compressed, and round 601 counts as round 44.
A run that breaks these rules is not accepted, whatever the round reached.

