Nightmare — Mod Description

The sun will not rise. It will never rise again.

Nightmare is a hardcore horror difficulty mod for Minecraft 1.21.1. When activated, the world is locked into permanent midnight and a supernatural entity — the Shadow — is unleashed to hunt every player in the world. It does not stop. It does not tire. It does not forget you.

This is not a mob mod. The Shadow is a single, persistent threat with layered AI, and it will adapt to how you play.

The Shadow

The Shadow is unlike anything in vanilla Minecraft. It makes no ambient sound. It is silent when hurt. It has no death cry. The only signs it is near are the distant thud of footsteps, the closing darkness at the edge of your vision — or the sudden silence before it strikes.

It stalks players from a distance, circling into blind spots and hiding near walls and trees. It watches. When it decides to move, it moves fast. It breaks down doors and opens trapdoors. It navigates water. It teleports. When hurt, it may feign a full retreat — only to return minutes later, more aggressive than before. In multiplayer, Shadows share information. If one spots you, the others will converge.

Darkness

The Shadow does not need to touch you to affect you. As it closes in on its target, darkness spreads. Get within 16 blocks of the Shadow while it is hunting you and your vision will begin to fail. Stray within 5 blocks of any Shadow, even one hunting someone else, and the same fate applies. Take a direct hit and the darkness intensifies further.

It Gets Worse

The longer the nightmare lasts, the stronger the Shadow becomes. Every in-game minute it gains speed and attack damage. Surviving a single night is tense. Surviving many is a different challenge entirely.

The Shadow also reacts to your behavior:

Sleep in a bed and it will materialize beside you.
Place a torch and it will retreat — then return and destroy it.
Hold a light source and it will keep its distance — for now.
Respawn after dying and it will already be waiting at your spawn point.
Occasionally it will speak. Brief, cryptic messages. It is aware of you.

Weaknesses

The Shadow is highly resistant to conventional weapons. It cannot be burned, drowned, or shot with arrows. However, it has known vulnerabilities:

Gold weapons deal 50% bonus damage.
Smite enchantment adds 15% bonus damage per enchantment level.

These are not accidents. They are the only tools that matter.

Multiplayer

Each player has their own Shadow — a dedicated hunter assigned only to them. Shadows are tracked individually and respawn for their assigned player after a configurable delay. The nightmare does not end until every Shadow across every player is defeated.

When only one player remains, they receive a burst of speed. A fighting chance. Shadows share spotted player positions with each other — finding one means others are already on their way.

Victory

Killing your Shadow does not end the nightmare — not until every Shadow across every player is defeated. When the last one falls, the sun rises again. All players are shown how many nights the nightmare lasted.

If that number is large, you earned it.

Setup

Enable with:

/gamerule nightmare true

Or use the command:

/nightmare enable

Or go to gamrules then to miscellaneous and find nightmare and enable it.

Disable manually the same way

Configuration

Setting	Default	Description
Respawn Delay	2400 ticks (2 min)	How long before a killed Shadow respawns
Teleport Distance	40–50 blocks	Range of Shadow teleportation
Heartbeat Range	32 blocks	Distance at which the heartbeat sound plays

NeoForge 1.21.1 · Java 21 · Server-side compatible

Nightmare (The Shadow)