To check the amount of entities in your world : 1. Go inside your world.
2. Navigate to the area that is laggy. If it's the game in general, skip to step 3.
3. Click F3 on your keyboard.
4. Look at the top left of the screen. There should be a capital "E". Next to the e there should be two numbers configured as such: x/x where the "x" represents the entity count. Look at the 2nd number. That shows the amount of entities in the immediate area.
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