Mob battles addon is a addon that makes users capable of making different mobs fight each other. Even modded or custom entities!

Step 1:

Find or spawn mob in quantity more than 2. Image Instruction:

Step 2:

Get the Red Team or Blue Team from the Items category;

Step 3:

Click (ATTACK) with either Blue Team or Red Team. The hit entity will get in a team based on your item (e.g hitting a husk with Red Team to make it join Red Team). Image Instruction:

Step 4:

Repeat Step 3 on another entity. Image Instruction: 

Step 5:

CLICK (ATTACK) with the Start Fight item on any entity

The mobs won't receive damage.Image Instruction