The only confirmed survival rule
Breet Studios tells you to stay silent, stay hidden, and survive. It also says each monster behaves differently and every room can hide a new threat. A plan that works on one creature can fail on the next. Do not borrow a chase speed from another ape game and expect it to hold here.
How to spend noise
Walking is the default that matches the published rule. Sprinting, jumping, and grouping up on one tile all make you easier to find if a nearby creature listens. That last part is a reading of "stay silent," not a measured hearing radius. No official hearing distance is published.
If the server is already loud, let that noise move away from you before you cross the hall it pulled a creature into. Tell teammates the direction you heard something, then stop talking. Twenty players is the server cap, so one screaming lobby can erase the headphone advantage.
Hiding
Pick cover before you need it. A useful spot still has a second way out. A dead-end closet matches the official warning that a room can hide a threat, and it also traps you if the threat is the one that enters.
Break line of sight, then wait. Leaving early because the hall looks empty is how a different monster, with a different behavior, catches the same route.
What the shop can and cannot do
A Radar, once you have bought one, is described as showing where monsters are. The Advanced Radar pass adds range and a beep when they get close. A beep is itself a sound. Use it to choose a quieter path, not as a cue to sprint at the marker.
A Speed Potion and the Infinite Speed Boost pass make you faster. Faster movement still has to obey the silence rule. The boost does not publish a stamina number.
A Noise Maker is described as making noise. Use it only when you want something to investigate a spot you can leave. A Flashlight is described as lighting dark rooms. The store text does not say whether light alerts monsters.
Death and items
The Survival Kit pass says you receive one random shop item when you respawn, with Speed Potion, Sonar, and Flashlight given as examples. That is the only published respawn grant. It does not say your whole inventory returns. Assume anything the pass does not mention can be gone.
Squad split
With two or three people, one player can watch the hall you just left while another checks the next room. Call the creature label if you recognize it from the showcase roster, then go quiet. A full 20-player server does not need a role plan. It needs less noise.