Features:

1. All creatures in the game now level up with the player.
(In vanilla, randomly, some creatures level up with player, and some don't. The ones that level up with player have broken stats)

2. All creature stats are carefully improved to be more scientifically realistic.
(Extremely carefully improved stats, good for both vanilla and heavily modded game)

3. Now, bigger creatures and animals have higher health and can deal more damage, extremely big creatures have much higher health. 
(You will not see a 900 hp adult mammoth anymore)

Ever getting annoyed by the broken vanilla level-up system?
Ever getting bored after 1 hit killing a bear in late game?
Ever wonder why mammoths are so weak compared to their gigantic size?

This is the lightweight long-waited creature balance mod - One mod to rule them all! 

Hard Requirement: Bears of the North (A version without requiement will be developed)
Please Endorse the mod which made the bears great again :)
If you don't have BOTN, then go to 
https://www.nexusmods.com/skyrimspecialedition/mods/108203
Credits: arwing0890


In vanilla, creatures do not have a proper level-up system, so they become extremely weak in late game. 
In this mod, generally, many creatures are stronger in early game, and will not become competely useless in late game.
Stats of Creatures are almost totally based on their size, not Bethesda's brainstorm. 

If creature A is bigger and weighs more than creature B in real life, then A would definitely have more health than B, and A's attack damage is also likely to be higher than B.

The damage animals can deal are based on their relative size and real-life abilities. 
For example, Bears in this game (which are similar to prehistoric Short faced bears) weigh over 1 tonne, therefore their health and strength are much stronger than the average 80kg humanoid creatures. 
While mammoths are huge, they move slower than predator creatures and were hunted by humans with hit-and-run tactics.   

All stats are carefully reworked, which suits both vanilla and heavily modded games.
Bigger creatures level up faster, smaller creatures level up slower


Notes: 
This level-up system does not affect some high-fantasy creatures like Dragon since it is difficult to weigh their stats based on a science-sense.
This level-up system does not affect some competely passive creatures like Chicken.

Relative power of some creatures in this mod compared(approximate estimate):

Humanoid (regular): 
Damage: ★☆
Speed: ★★★★
Health:★★
Armor/Skin/Shell/Resistance:★★★★★
100+HP dude with Steel sword in early game

Humanoid (Hero): 
Damage: ★★★★
Speed: ★★★★
Health: ★★★★★★★★
Armor/Skin/Shell/Resistance: ★★★★★★★
Estimated stats of a decent but not ridiculous follower or character 

Wolf: 
Damage: ★
Speed: ★★★★
Health:★
Armor/Skin/Shell/Resistance: ☆
Number is their advantage 

Mudcrab: 
Damage: ★
Speed: ★
Health:★
Armor/Skin/Shell/Resistance: ★★
Always eat crabs after removing the shells unless the crab is tiny enough

Horker :
Damage: ★★★
Speed: ★
Health: ★★★★★★★★★★★★★★
Armor/Skin/Shell/Resistance: ★★
Harmless

Sabre Cat: 
Damage: ★★★★★
Speed: ★★★★★★
Health:★★★★★
Armor/Skin/Shell/Resistance: ★
Big cats kill their prey faster than bears of similar size in real life

Smilodon (Mihail's mod):
Damage: ★★★★★★
Speed: ★★★★★★
Health: ★★★★★★★★★★★★★★
Armor/Skin/Shell/Resistance: ★
Prehistoric big cat, a stronger sabrecat(According to Mihailmods' description), a terrifying predator 

Bear (from BOTN): 
Damage: ★★★★★★
Speed: ★★★★★
Health: ★★★★★★★★★★★★★★★★★★★★
Armor/Skin/Shell/Resistance: ★★
Those bears are almost unchallengable on land due to their massive size (de facto Short-faced Bears)

Mammoth : 
Damage: ★★★★★★★★★★★★
Speed: ★★
Health: ★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★
Armor/Skin/Shell/Resistance: ★★★★
Not huntable if you fight them with a sword and a sheild, but huntable with hit-and-run tactics, just like what ancient humans did 

Megalodon (Birbwalker21's mod): 
Damage: ★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★
Speed: ★★★★★
Health: ★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★
Armor/Skin/Shell/Resistance: ★★★★★
Most powerful creature ever existed on planet Earth



More creature improvements are on the way!
The upcoming ones will include level-up systems, AI-reworks and stat-reworks for other creatures mods!
E.g. wonderful creature addons from Mihailmods and Birbwalker21

Upcoming patches:
Birbwalker21's Megalodon, Tuna Fish, Trilobites.......
Mihailmods' Penguin, New Mammoths, Guars.......
Sea of Spirits
and much more......

Compability:
SkyTEST 2022 Redux - Realistic Animal and Predators 4K- 100% Compatible with the patch under optional files
I recommend using this Redux version instead of the old SkyTEST

Savage Skyrim - Not compatible
Any mod that adds new creatures is compatible


Credits: 
JPSteel2
Birbwalker21
Mihailmods
XilaMonstrr
etayorius
SpikeDragonLord 
jboyd4 
RustyShackleford 
AerynnRavanna 
Hannes821
Tooneyman