If your looking for a addon to make survival harder without adding new mobs and performance friendly, this is the perfect addon for you to upscale the difficulty above hard mode

This addon superbuffs 8 hostile mobs, changes 7 mob, buffs a tameable mob and adds 2 Misc mobs

The 5 hostile mobs and 3 changed mobs will spawn with full armor but each will be randomized based on their rarity, for example leather is most common armor to spawn with and netherite is the rarest, which can also be enchanted but at a low chance to spawn with enchanted armor and they will also spawn with different types of weapons and just like armor the better the weapon the lower the chance they spawn with it and they can spawn with an enchanted weapon just like the armor

You can also tame all of the hostile,changed and buffed tameable mob by using a Enchanted Golden Apple and for the buffed tameable mob you can just tame it with bone(I think you know who it is now) and heal them respectively of their type for example Zombie can be healed by rotten flesh and Skeletons can be healed by bones

List of Hostile Mobs:

Zombie:

HP boosted to 45 and can inflict poison damage for 5 seconds upon hitting a mob and player. They can also drop more unique items upon killing it

Skeleton:

HP boosted to 30 and can spawn with trident(enchanted) sometimes and enchanted bow,they can also drop Enchanted golden apples

Husk:

HP boosted to 45 and inflict the usual hunger debuff. They can also drop unique items upon killing it like the Zombie

Stray:

HP boosted to 30 and inflicts the usual slowness debuff and can also spawn with trident, they can also drop enchanted golden apples very rarely

Zombie Villager

HP boosted to 45 and inflicts poison just like the Zombie

Changed Mobs:

Parched:

HP boosted to 45 and now are neutral towards player and they attack other undead and monsters, helping the player and their spawn egg can be dropped by Zombie at a very low chance and can also spawn with tridents

Wither Skeletons

HP boosted to 40 but they still attack players and inflict wither effect but now they can attack monsters and undead when nearby

Blaze:

HP boosted to 40 and still attack players but their overall attack is strengthened and tend to prioritize at one spot(I personally don't recommend you tame it)

Pillager:

HP boosted to 40 and can have higher chance spawn with enchanted crossbow, and can drop more variety of loot

Vindicator

HP boosted to 30 and can have randomized armor points and damage, and can drop more variety of loot

Witch:

HP boosted to 50 and can drop more variety of loot

Enderman:

Increased HP slightly

Buffed Tameable Mobs:

HP increased to 25 and overall attack improved and can attack monsters when untamed

Misc Mobs(extra):

Iron Golem:

Slightly boosted HP and is tameable by golden apple(normal)

Wandering trader:(OP)

New trades and trades enchanted books,items which require luck and many other beneficial items,helping players survive the harder difficulty(wandering trader will be rebalanced as updates come)

wandering traders share the same trades to avoid RNG

Oh and also Zombie,Zombie Villagers,skeletons,stray, vindicator and husk can drop exclusive weapons upon killing them at a very low chance(Vanilla high tier Enchantments Sword)

Illagers can spawn randomly in patrol groups at a very low chance during daytime in overworld(pillager may be the only one to spawn naturally due to unknown issue)

Undead mobs tend to react slower than other mobs

It is recommended to use bonus chest unless you want a true challenge

NOTE:

THIS ADDON IS ACHIEVEMENT FRIENDLY

THIS ADDON DOES NOT REQUIRE EXPERIMENTAL TOGGLES

YOU CAN MODIFY/EDIT THE DOWNLOADED ADDON FOR YOUR PERSONAL PREFERENCE

THIS ADDON SUPPORTS VERSION 1.26+

YOU CANNOT REDISTRIBUTE THE ADDON WITHOUT CREATOR CONSENT

YOU CANNOT CLAIM THIS ADDON AS YOURS

IF YOUR MAKING A REVIEW ON YT ABOUT THIS ADDON MAKE SURE TO PASTE THE LINK OF ADDON DIRECTING TO CURSEFORGE

Undead Arise [Simple]