Build 42 Stealth & Noise — Crouch, Lightfooted, Nimble, and What Attracts Zombies

Build 42 rebuilt stealth from the ground up: light, weather, and cover now genuinely matter, and the three movement skills each do something specific instead of all feeling like "be quiet." Yes — a properly built sneaky character can slip past zombies that a loud one would never survive. This guide covers how detection and noise actually work on 42.20, what each skill changes, and which traits and occupations stack with them. Facts cross-checked against stable 42.20.0 on 2026-08-05, with skill numbers from current B42 references.

How detection works in Build 42

Detection has two channels — vision and hearing — and Build 42 added real levers for both:

• Light and weather: darkness cuts zombie line of sight, fog lowers it further, and storms dampen their hearing. Lanterns and torches work as powerful zombie lures at night, so carrying one is a decision, not a free buff. Cat's Eyes is a strong pick for the dark nights B42 makes genuinely dark.
• Cover: hiding behind objects — cars, fences, walls — genuinely improves visual stealth now. Crouching next to a wall or vehicle lowers your profile further.
• Zombie variety: zombies roll random hearing, speed, and vision, so some can be brushed past while others react instantly.

The three movement skills: what each actually does

The classic mistake is treating them as interchangeable. Practical split: level Lightfooted if you walk or run near threats; level Sneaking if you live in crouch and care about being spotted; level Nimble for combat-stance speed with a quieter-feet side benefit. Gymnast boosts Lightfooted and Nimble; Hunter boosts Sneaking — they are not the same skill.

The footstep noise stack

Footstep loudness is a multiplier chain, not a single stat. For a crouch-walk near zombies the practical stack is:

1. Graceful trait: ×0.6 step volume.
2. Crouching: further multiplies by Sneaking's crouch factor (~1.14 at Sneak 0 → ~0.48 at Sneak 10).
3. Lightfooted level factor: 0.99 → 0.20.
4. Nimble: quieter as it rises (×1.0 → ×0.5).
5. Indoors: being inside a room halves the world-sound radius after all other math.

Maxed out (Graceful + crouch + Sneak 10 + Lightfooted 10 + Nimble 10), crouch steps are theoretically ~99% quieter than base — but the game still checks sight, and doors, fights, vehicles, and guns drown out any stealth build. Lightfooted 10 is not "invisible to hearing"; it still leaves you audible at close range.

Leveling the stealth skills

• Sneaking XP comes from moving undetected near zombies that could potentially notice you — crouch-walking through a cleared field with nothing around grants little or nothing. Crouching next to a wall is concealment, not an XP source.
• Lightfooted levels from moving while zombies are nearby.
• Nimble only levels in combat stance, but its movement bonus now applies everywhere.

Endurance matters: crouching costs more than walking, and an exhausted crouch-run gets you spotted when you are forced to rest in the open. Keep a reserve for the escape.

What attracts zombies to a base

Attraction is four separate systems, not one "base magnet":

For sandbox players who want a quiet run: Hearing, Sight, Follow Sound Distance, Redistribute Hours, Helicopter, House Alarms Frequency, and Firearm Noise Multiplier all tune these channels directly.

Verified on 42.20 · Last checked 2026-08-05

Detection mechanics, the three skill roles, and the footstep multiplier order come from current B42 stealth references and PZwiki (42.18-era stamps), cross-checked against stable 42.20.0 (July 29, 2026). The theoretical max-stealth figure is a community calculation and includes neither environmental randomness nor zombie stat rolls — treat it as a ceiling, not a guarantee.