Minecraft Java 1.21 Mods
Browse 26 free mods for Minecraft Java 1.21 — popular picks include CobbleBoss, Terra Entity, Unknown5473lib.
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CobbleBoss
A mod that allows you to infinitely add and customize your own exclusive Bosses in the Cobblemon world.
Terra Entity
A mod encompasses numerous Terraria monsters and bosses, and constitutes one of the submodules integrated within the larger mod, Confluence.
Unknown5473lib
A universal code library prerequisite for mods created by Unknown5473,Provides a Boss mob template library and screen effects..
MythicMobs
Create custom mobs and bosses with advanced skills, attributes, equipment, and more!
Cataclysmic Arsenal - Epic Fight
Redesigns Cataclysm weapons and armor, adding passives and traits based on thematic bosses, allowing them to work with the Epic Fight system.
Nice Huds
Bossbar Huds for players holding Clocks, Compasses and Recovery Compasses. Also adds a calendar/time based event system including seasons.
Styled Boss Bar API
Design your Styled Boss Bar!
xBossBar
Create, edit and show custom BossBars with a few commands, All on a single plugin.
Bossbar Lib
A simple bossbar library allowing for per entity bossbars
AutoMessageSystem
Full auto-message system! Chat, BossBar, Title and ActionBar! PlaceholderAPI support!
The Mob
Mob Framework | YAML | Boss Phases | Radar HUD | AutoSpawn | Player Stats | 1.21.+
AnnounceX
📢 Professional announcements with custom durations, colors, sounds & particles! Title + BossBar modes. Perfect for events! ⚡
♂️ TheMob ✦ Advanced Custom Mobs & Bosses
Mob Framework | YAML | Boss Phases | Radar HUD | AutoSpawn | Player Stats | 1.21+
CustomHitboxLib
A powerful Forge 1.20.1, NeoForge 1.21.1 library that adds true multipart hitboxes to any entity! Override vanilla's single-square limitation and create complex bosses with precise collision using simple JSON Datapacks or the developer API.
![EnchantedBosses [Free]](https://pub-2ae937f770284535a96c3330f91236aa.r2.dev/thumb/modrinth/154027.webp)
EnchantedBosses [Free]
An endlessly customisable bosses plugin using SkillsLibrary
ADKM
Defeat a powerful, giant boss roaming your world to claim his legendary Scythe with +16 Attack Damage! A high-risk, high-reward challenge. (Requires GeckoLib)
Custom Boss Zoryth AI
Zoryth AI Boss is a premium, high-performance custom boss framework for Paper (1.21.x).
Vitae
Vitae is a data-driven entity framework for NeoForge 1.21.1 that lets you define custom animated mobs, bosses, and NPCs through datapacks and optional KubeJS scripting.
BossReng's UI Mod
Boss_Reng and various Lofi music creators bring you the best visuals and the most comfortable acoustic experience in Minecraft!
NxControl
NxControl is an advanced staff plugin that lets OP players control players or mobs using simple keybinds, with GUI, bossbars, and freeze system built-in. It’s lightweight, powerful, and perfect for moderation, trolling, or cinematic gameplay.
Custom Entity API
A datapack API allowing anyone to add custom entities, or bosses, to Minecraft: Java Edition, powered by Animated Java.
Item Challenge
Give your server a collective goal: collect a set amount of any item before the in-game days run out. Track progress in real time through a boss bar, deposit your items in one command, and see who contributed the most.
Lumo (FREE) | KI-Chat mit Groq API (LLM) | Multilingual | Bossbar | Logging
ChatBot | KI-Chat | Lumo | Multilingual
Flame Announcer
A powerful and highly customizable announcement plugin featuring scheduled Chat, BossBar, and Interactive clickable messages with full in-game management.
Spell Utils Mod (1.21.1) – Library for Iron's Spells and Spellbooks Addons
Spell Utils Mod is a utility API designed to help developers create addons for Iron's Spells and Spellbooks Mod. It provides ready-to-use systems, classes, and tools that simplify the process of building custom spells, mobs, and bosses. This mod is mainly intended for mod developers, not regular players. Features: Mob & Boss Systems Custom spellcasting […]
FDLib Mod (1.21.1, 1.20.1) – Code for Cinematic Bosses
FDLib provides a collection of shared tools and systems that other mods need to work properly. This library adds features like model and animation loaders, client-side cutscenes, custom boss bars, and configuration options. It serves as a foundation that certain mods require to function. Features: Adds a loader for Bedrock models and animations. Supports client-side […]