CSM - Client Side Mobs

By
MisoPy

This is a mod that adds mobs that operate entirely on the client-side.

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Description

Client Side Mobs [EXPERIMENTAL]

>> CRITICAL WARNING: EXPERIMENTAL PROJECT <<

This mod is an entirely EXPERIMENTAL Proof-of-Concept.

It attempts to simulate complex entity behavior (Boss fights) entirely on the client-side. Because of this unorthodox approach, it may cause visual desyncs, unexpected behavior, or false-positives with server-side movement validation plugins (Anti-Cheats).

USE AT YOUR OWN RISK. The developer takes no responsibility for any server bans or kicks resulting from using this mod on public multiplayer servers.

📖 About The Mod

Client-Side Mobs allows you to experience thrilling boss fights without needing to install anything on the server. The boss entity, its AI, its attacks, and the damage calculations are all simulated entirely on your client!

To start the boss fight, simply type: /csm boss

☆ Features

Client-Side Simulation: The boss exists only on your screen, meaning it works on any server or single-player world.
Custom AI & Attacks: The boss features dynamic phases, gap-closers, AoE explosions, and a massive ultimate attack!
Immersive Visuals: Intense particle effects, custom sounds, and screen shake to make the fight feel impactful.
Skill Points & Upgrades: Defeating the boss grants you Skill Points (SP) which can be spent in a custom GUI to upgrade your Base HP, Attack Damage, or Reach.

⚠ Known Issues & Incompatibilities

Because this mod uses a highly unorthodox and unconventional approach to simulate entities and combat locally, it essentially bypasses or overwrites standard vanilla mechanics on the client. As a result:

Mod Compatibility is NOT Guaranteed: This mod may conflict with other mods that heavily alter combat mechanics, rendering, or player status (such as custom health or damage overhauls).
Visual Desyncs: You might experience occasional visual glitches or desyncs, especially if the server is lagging.
Fake Death Screen: The mod fakes a death screen when you "die" to the boss without actually dying on the server. Other mods interacting with death events will not trigger.

⚙ Experimental Commands & Anti-Cheat Compatibility

Since this mod simulates combat locally, taking knockback from a client-side entity is normally impossible without causing server desync. You can toggle experimental knockback in-game via command: /csm config doKnockbackPackets <true|false>

When False (Default): Safe to use. The boss will deal damage to you, but you will not take physical knockback.
When True: The boss will knock you back! However, this sends artificial velocity packets to the server. Movement validation plugins (like Grim) will flag this and rubberband you. Only enable this in single-player or on private servers where you have permission.

This project was created as an experiment in pushing the boundaries of what is possible exclusively on the Minecraft client. Feedback and bug reports are welcome, but please remember its experimental nature!