Enhanced AI

All mobs

Anti-Cheese

Mobs with this feature enabled (by default all monsters) will break boats and minecarts they're stuck in.
Can be configured to prevent mobs from being minecarted or boated.

Explosion Avoidance

All mobs will run away from a creeper about to explode or an ignited TnT

Break Anger

Zombified Piglins will get angered when a closeby player will break quartz ore.
Configurable to make any set mob target a player breaking specific blocks.

Fishers

Mobs with a Fishing Rod will be able to reel in players. By default only Zombies can spawn with a Fishing Rod.
When reeled, there's a chance that items in the target's inventory are reeled instead of the target.

Custom Mob Fleeing

Any mob can be configured to run from any other mob. By default there's no custom mob fleeing.

Leaping

Disabled by default because it's just a draft, makes mobs make a small jump towards the target.

Miners

Mobs are able to mine their way to the target. By default only zombies can and are equipped with a Stone Pickaxe.

Movement

Mobs that reach a climbable block will now be able to climb it (ladders, vines, etc)
Also mobs have 15% bonus movement speed and 250% bonus swim speed

Pearlers

Mobs with ender pearls will be able to use them to reach the target. By default only zombies can spawn with 3 ender pearls.

Riding

Some mobs are able to mount other mobs. By default only Spiders can be ridden and Zombies, Creepers, Husks, Zombie Villagers, Drowneds, Skeletons, Strays and Cave Spiders are able to mount.

Targeting

Mobs have enhanced targeting capabilities.
They have increased sight (can see targets from farther away) and can also sense targets through walls.
Mobs also have better targeting when hit (e.g. Creepers will now switch taget if who hit them is closer).
Also mobs will no longer fight eachother, have a small chance to be neutral and are affected by blindness effect.

Biters

Zombies (by default) are able to bite entities that hit them without a weapon.

Item Disruption

Mobs that hit an entity are able to disarm it. By default only enderman can do that.

Melee Attacking

Attack range is now affected by the forge:entity_reach attribute and also the attack speed attribute.
Also mobs use the new 1.20.2 attack changes.

Open Doors

Mobs are able to open doors. By default only long noses mobs can.

Spawning

Min spawn distance has been increased and max has been decreased, so mobs will spawn more closer to the player.

Warden Interactions

Mobs flee from the Warden.

Animals

Scared and Attack

Some animals will flee from players on sight, whilst others will attack back.

Group Flee

If an animal is attacked all the other animals of the same type around will flee or attack back

Not tempted

Some animals are not temped by food

Blazes

Attack

Blazes have randomized parameters when shooting fireballs. Can shoot more, less, faster, slower, have more/less inaccuracy ...

Bugs

Silverfish

Silverfishes will call for more silverfishes when hurt and faster.

Creepers

Swell

Creepers have a chance to spawn with the ability to ignore walls, breach, walking while exploding or the ability to throw themselves at the target.

Drowneds

Swimming

Drowned swimming is faster and uses the swim speed attibute instead of the movement speed one. Also the AI for swimming should be a little better.

Endermen

Get Over Here

Disabled by default, endermen teleport players if they can't reach them

Ghasts

Shooting

Ghasts can shoot up to 3 fireballs and might be able to shoot when they can't see the target (breach)

Illagers

Pillagers Shoot

Change the shooting range, cooldown and inaccuracy of Pillagers

Pillager Fleeing

Pillagers can flee from the target and attack while fleeing

Ravagers

Ravagers breakable blocks can be set with a block tag

Pets

Snow Golems

Shoot faster, deal damage with snowballs, freeze enemies and heal other snowmen

Iron Golems

Have an innate 40% damage reduction and fire lasts less

Wolves

Wolves have double hp and damage

Shulkers

Attack

They can shoot faster

Armor

Shulkers have increased armor, 30 when closed (20 in vanilla), 20 when peeking (0 in vanilla) and 10 when open (0 in vanilla)

Bullets

Increases levitation duration and amplifier given by bullets

Skeleton

Shoot

Change the shooting range, cooldown and inaccuracy. Also small chance for a skeleton to spawn as a spammer

Fleeing

Skeletons can flee from the target and attack while fleeing

Wither Skeletons

Have a chance to spawn with a bow and and arrows give wither instead of fire

Slimes

Slimes

They can spawn bigger and jump faster

Spiders

Webber

Some spiders are able to throw slowing webs at targets

Misc

Spiders take -90% fall damage

Villager

Attacking

If too low reputation, villagers will attack the player

Withches

Dark Arts

Some witches can spawn with the ability to use dark arts. Will use a spawn egg to spawn a Villager and will lightning strike it to transform it into a Witch

Throwing Potions

Witches will be smarter at throwing potions. Can also throw two in a row, lingering ones and wrong ones. Can also use slow falling when falling.

Thirsty

Can drink potions smarter

Fleeing

Witches can flee from the target and attack while fleeing