Somewhere in gnembon's Simple Hostile Mob Farms, Minecraft 1.12 (Fun Farms Ep. 15) video he mentions difficulty and local difficulty but I cannot remember where in the video.

In my 1.12 survival world I ran my build of his farm for an hour, getting about 4600 items/hr on Normal and about 6500 items/hr on Hard (regional difficulty 3.19, which is much lower than the max of 6.75). I ran the Normal test before the Hard test so the local difficulty may have changed slightly. Some of this effect might be due to pack spawning or just higher spawn rates.

The answers from Advantages of hard mode in minecraft are outdated.

I am looking for evidence based answers (tests, looking through game code), not hearsay or what the wiki says if it is unsourced.

2

2 Answers

Yes, hostile mobs will spawn more when on hard mode than easy and normal mode.

8

No, spawn rates are not affected by difficulty.

However, there are effects of harder difficulty on spawned mobs, including (but not limited to):

• Chance of spawning with armor
• Chance of spawning with enchanted weapons
• Zombies and skeletons are more likely to pick up loot
• Slimes are more likely to be larger
• Spiders can spawn with speed, strength, regeneration or invisibility
• Zombies can spawn with reinforcements

I found these by searching for usages of the getSpecialMultiplier method in net.minecraft.world.DifficultyInstance.

I did not include any code snippets because you can't publish decompiled Minecraft code.