Global difficulty
The global difficulty is split into steps. The activated steps is determined by the players' deaths. This difficulty is for every player.
Each time a player dies, the number of deaths is increased. If a step is reached, it is activated.
If no one dies during 12 hours, the latest activated step is disabled. For example, if you are at 15 deaths and the two latest steps were activated at 10 deaths and 13 deaths, after the decrease, the number of deaths will be 10.
Easy steps
0 death Phantoms are disabled. All blocks drop after a block explosion or a mob explosion. Difficulty is easy. At least 30% of connected players must sleep to skip the night.
1 death Difficulty is normal.
2 deaths At least 70% of connected players must sleep to skip the night.
3 deaths Difficulty is hard.
5 deaths All blocks do not drop after a block explosion like bed (except TNT) or mob explosion like creeper. Phantoms are back. (This the vanilla "Hard" difficulty.)
Ominous steps
7 deaths Increase mobs' follow range by 25%. Skeletons are more intelligent.
8 deaths Increase fall damage by 25%.
10 deaths Remove one heart.
12 deaths Increase mobs' step height to 1.1.
13 deaths All blocks do not drop after a TNT explosion.
15 deaths Increase mobs' reinforcement by 25%. Zombies are more intelligent.
16 deaths Debug screen (F3) is reduced. You cannot get your coordinates.
18 deaths Increase fall damage by 50%.
Dangerous steps
20 deaths Remove another heart (2 removed).
22 deaths All players must sleep to skip the night. Charged creepers start spawning.
23 deaths Increase mobs' follow range by 35%.
24 deaths Disable infinite water source.
25 deaths Increase mobs' reinforcement by 50%.
26 deaths Increase mpbs' step height to 1.5.
Evil steps
28 deaths Limit crafting to unlocked recipes. Piglin brutes start spawning.
30 deaths Enable universal anger.
32 deaths Increase fall damage by 100%.
33 deaths Increase mobs' reinforcement by 75%.
35 deaths Increase mobs' follow range by 100%. Creepers are buffed.
No returns steps
37 deaths Never forgive dead players.
40 deaths Disable natural regeneration.