Not a Bug
Your game isn't broken. At random moments something goes wrong on purpose: inverted controls, a tilting camera, lightning next to you, a mob behind your back. 48 pranks, client-side, works on any server. Panic key: DEL.
- Loaders
- Fabric
- Downloads on Modrinth
- 142
- Followers on Modrinth
- 2
- versions
- 2
- Updated
- October 3, 2026Oct 3
- Published
- in 2026
At a glance
Install in the game only; not needed on the server
🐛 Not a Bug
No, your game is not broken. Something is going wrong on purpose — and it will stop before you can prove it.
At a random moment — you never know when, and you can tune how often — this mod does exactly one thing to you: inverts your controls, tilts the horizon, drops lightning next to you, puts a mob behind your back. Then it puts everything back the way it was. Nothing is logged. Nothing is left behind. You just look slightly insane in voice chat.
68 pranks. Client-side only: it works in your own world and on any server you join, without the server knowing anything about it.
Panic key: DEL. Stops everything instantly, always.
🕯️ New in 0.3.0 — The Paranoia Update: a mob that only moves when you're not looking, a fake totem, loot you can't pick up — plus a settings screen, haunting mode and full English/Spanish texts. See the changelog.
🎮 Your hands
- Reversed controls — W is S and A is D
- Mirrored strafe — only the sides swap, which takes much longer to notice
- Swapped jump and sneak — space drops you to the floor, shift launches you
- Inverted / hyper / molasses mouse — flipped axes, 4× sensitivity, or 0.15×
- Cinematic camera — vanilla's smooth camera, kicked on without asking. Aiming becomes impossible
- Drifting aim, forced sneak, sticky forward, hiccups, spin around
🎥 Your camera
- Slow spin — the sneakiest one in the mod. It rotates so slowly you never catch it starting; you just notice the horizon is not where you left it
- Dutch angle — the world tilts 8–25° and nobody can say what's wrong
- Upside down — 180°, held
- Whiplash — a hard snap to one side with two decaying bounces
- Pendulum, nervous camera, earthquake, barrel roll, dolly zoom, tunnel vision, fish eye
The camera moves — your aim doesn't. Shaking never makes you miss a block.
💀 Your screen
- Jumpscare — a full-screen creeper, enderman or Herobrine face, with the scream
- Fake crash — a Java stack trace, for two seconds, and then nothing
- Screen crack, blackout, phantom hit, hidden HUD
- Inverted colours, creeper vision, spider vision, blur
- TV static — white noise and "NO SIGNAL" for a second
- Rogue cursor — a mouse cursor wanders across your screen, clicking things. Yes, it looks like someone else is controlling your PC
- Cutscene — cinema bars close in with *"Directed by "*
- Fake totem — the totem of undying animation, particles and sound, as if you'd just cheated death. You hadn't
- Fake disconnect — "Connection lost…" for two seconds, with vanilla's own text
🔊 Your ears
- Creeper behind you — a hiss right against the back of your neck, and then… nothing. The joke is the second and a half you spend looking for it
- Heartbeat — yours, getting faster, while absolutely nothing happens
- Ghost footsteps — something walking behind you
- Haunted / party jukebox — disc 11 and 13, or Pigstep and Lava Chicken
- Deafness — absolute silence for five seconds. No footsteps, no ambience, no music. Worse than any sound
- Whispers — low voices right behind you
- Inventory rummage — someone going through your chest behind your back
- Steps above — footsteps right over your head. In a cave, the worst one
🌍 Your world
These effects put something in your world. Everything is created only on your client — the server never hears about it, nothing can hurt you, and it removes itself. Not a single real block ever changes.
- 🕵️ Intruder — the star of 0.2.0: a full 30-second scripted sequence. "Steve joined the game" → footsteps approaching from behind → someone mines a block of your wall, crack stage by crack stage (and stops — nothing breaks) → a chest opens and closes → the footsteps walk away → "Steve left the game". The chat lines use vanilla's own translation keys, so they look identical to the real thing in your language
- 👀 Watcher — a mob appears 15 blocks away in your peripheral vision, standing still, facing you. The moment you actually look at it, it's gone
- 🗿 Weeping angel — a mob that only moves when you're not looking. Every time you look away it's closer. When it reaches you it's gone — and something breathes on your neck
- 💎 Fake loot — a diamond on the ground in front of you. You can't pick it up. When you get close, it vanishes
- 🌀 Fake portal — portal particles, the portal sound and a purple haze, as if you were about to change dimension
- ⛏️ Ghost miner — someone is mining your wall: real crack stages with the real pickaxe sound of that material… then it stops. Block intact
- 💥 Phantom break — a block behind you bursts into particles with its breaking sound. You turn around: intact
- 🧨 Fake TNT — a primed TNT appears at your feet, blinking and hissing… and fizzles out
- 🐔 Chicken rain — 12-18 chickens fall from the sky, clucking. They leave on their own
- 🔊 Distant explosion — a boom in the distance, explosion particles, a camera shake. Nothing exploded
- ⚡ Lightning strike — a real vanilla lightning bolt in visual-only mode lands 6–12 blocks away: the actual blue bolt, the actual thunder, plus a white-blue flash that blinds you for a moment
- 👁️ Ghost mob — a mob appears behind you, standing still, facing you, and leaves after two seconds
🗣️ Lies
Fake chat messages nobody typed, invented system toasts, fake on-screen titles, a storm of five absurd toasts in two seconds, and a renamed game window — that last one you don't find until you alt-tab half an hour later.
⚙️ Settings screen & haunting mode
Every option and every single effect has an on/off switch in the settings screen — open it from ModMenu (optional dependency) or with /notabug config. No JSON editing needed.
Haunting mode (off by default): pranks get more frequent and the scares weigh more the longer you play, maxing out at 45 minutes. Resets when you leave the world. For the horror crowd.
All in-game texts are in English and Spanish, following your game language.
🛟 It always gives everything back
This mod breaks your controls on purpose, so cleaning up is the part that got the most care:
DELcancels everything currently running, instantly- Disconnecting or quitting to the menu cancels everything too
- It never writes to
options.txt. Your keybinds, mouse sensitivity and brightness are never modified — the input is faked in memory instead, so if the game closes mid-prank you don't wake up with W and S actually swapped - It never touches your world, your inventory or your held item
- It sends no packets of its own
⌨️ Commands
Client-side commands — no server permissions needed.
/notabug status, next prank, what's running
/notabug on | off
/notabug panic stop everything (same as DEL)
/notabug now [id] fire one right now, random or by name
/notabug list all 68, with family and on/off state
/notabug config open the settings screen
/notabug intensity 0.25-2.0
/notabug interval <min> <max> seconds between pranks
/notabug disable <id> | enable <id>
/notabug reload⚙️ Config
config/notabug.json, created on first launch.
| key | default | what it does |
|---|---|---|
minSeconds / maxSeconds | 90 / 300 | how often something happens |
intensity | 1.0 | 0.25 mild, 2.0 unbearable |
allowScares / allowPranks / allowWeird | true | turn off whole families |
disabledEffects | [] | specific ids you never want to see |
singlePlayerOnly | false | stay quiet on servers |
onlyWhenFocused | true | never fires while you're in another window |
announceEffects | false | print the id in chat when one fires |
comboChance | 0.15 | chance of two at once |
haunting | false | pranks escalate with session time |
chatMessages | [] | your own fake chat lines — {player} is your name; empty = built-in pool in your language |
Recording a video? Set announceEffects to true and /notabug interval 20 45. You'll see every id as it fires and can note the ones you want to cut.
Want only the funny half? allowScares: false keeps the pranks and drops the jumpscares.
📋 Requirements
- Minecraft 1.21.11
- Fabric Loader 0.19.0+
- Fabric API
- ModMenu (optional, for the settings button)
- Client-side only — do not put it on a server, it does nothing there
⚠️ Known issue with Iris
Four effects (invert_colors, creeper_vision, spider_vision, blur_vision) use vanilla's post-processing chain. With an Iris shader pack loaded they may not show up, because Iris replaces that pipeline. The other 64 don't care.
FAQ
How to install Not a Bug?
Install Fabric for your Minecraft version, download Not a Bug for the same version and loader, put the file into the mods folder and launch the game with the loader profile.
Which Minecraft versions does Not a Bug support?
Not a Bug has builds for Minecraft 1.21.11.
Is Not a Bug needed on the server?
Client only — no need to install it on the server