What a letter means here
Weapon letters are an editorial loadout order based on published roles: splash wonder weapons, Pack-a-Punch rifles and SMGs, early pistols, and guns that fall off. Perk letters follow the same idea from printed effects, with Juggernog first because it raises health from 100 to 250. Map letters are only the printed XP percent. A high XP letter is not a recommendation to learn the game there. Bus Depot is 125 percent and has no perks.
S tier
Player decision Take it when the box offers it and Pack-a-Punch it for high rounds. Do not spend every point fishing for it before you own Juggernog.
Player decision Treat it as a box priority on maps that include it, with the same ammo caution as the Ray Gun.
Player decision Use it in tight maps when you can see past the fire. Keep a second gun for crawlers and revives.
A tier
Player decision Keep it if the box gives it before a Ray Gun. It is not documented as splash.
Player decision A default primary when no wonder weapon is in the box.
Player decision Buy it when it is the wall gun on your loop. It is the refillable half of a wonder-weapon loadout.
Player decision Use the wall copy as a reliable primary if the box is moving.
Player decision Same job as the MP40 when the MP40 is not on the wall.
Player decision Buy it on Poolrooms. It is not a general-lobby gun.
Player decision Buy it on Backrooms before a long page route. Pack-a-Punch it after the pages open the machine.
B tier
Player decision Good mid-round burst. Do not make it the only gun past the point where that one-shot claim stops.
Player decision A known price on Overlook if the box is a bad spin. It is not ranked above a Pack-a-Punched wonder weapon.
Player decision Use it early. Replace it before a high-round attempt.
C tier
Player decision Replace it once a wall SMG or the box gives you a primary.
Player decision Knife beside it early. Do not spend 5,000 points upgrading it before the primary.
Player decision Same rule as the M1911. Swap it out by the time doors start costing 1,000 or more.
D tier
Player decision Do not build a round-15 attempt around it.
Player decision Skip it for the loadout. A normal knife already covers rounds 1 to 4.