Boids

Boids

Boids simulation for flocking fish 🐟

2.5M downloads
Created Apr 9, 2026
by Tomate0613

About

Boids

This mod replaces the vanilla fish behavior of flocking fish with a boids simulation.

A flock of fish in front of a white concrete wall

<a href="https://modfest.net/1.20"> <img src="https://raw.githubusercontent.com/ModFest/art/3bf66556e674d670e30f647d6a48c4e1798c21d4/badge/128h/ModFest%201.20%20Badge.png" width="179" alt="ModFest 1.20"> </a>

What's a Boids Simulation?

A "boids simulation" refers to a computer model that simulates the flocking or herding behavior observed in nature, like the coordinated movement of birds or fish. In the context of this mod, it means fish will exhibit more realistic and dynamic group movements, making your aquatic environments come to life.

In particular, each fish will follow these three rules:

  • Separation: steer to avoid crowding local flockmates
  • Alignment: steer towards the average heading of local flockmates
  • Cohesion: steer to move towards the average position (center of mass) of local flockmates

Additional Resources

You can learn more about boids simulations here:

Versions

v2.0.1+1.21.11Latest
1.21.11fabricFeb 20, 2026

- Fix #23 (Incorrect fish grouping) - Update fmj

Download
v2.0.3+1.21.2
1.21.2, 1.21.3, 1.21.4, 1.21.5, 1.21.6, 1.21.7, 1.21.8fabricFeb 20, 2026

- Fix #23 (Incorrect fish grouping) - Update fmj

Download
v2.0.4+1.21
1.21, 1.21.1fabricFeb 20, 2026

- Fix #23 (Incorrect fish grouping)

Download

Download

Download v2.0.1+1.21.11

Minecraft: 1.21.11

Loaders: fabric

Tags

fabric1.21.71.21.81.21.91.21.101.21.11
Boids - Orca Mods