Elements

Here is each element as what it does and the first creature to use it

Earth(projectile damage immunity)

Fire(Fire damage immunity)

Air(fall damage immunity)

Water(Suffocation immunity)

Enthropy

Structure

Volcanic (everything in this element has glow texture, and its breeding items are stone related blocks) (Basalt Stomper)

Cosmic (immune to the void)(warped snapper)

Plant (can cut down trees and or harvest crops for you)(Giganotosuchus)

Explosion (Breeding item is gunpowder and can use explosive projectile attack)

Steel

Electrical (gains special buffs when struck by lightning, buffs also apply to rider)

Steam

Darkness (everything in this element does bonus damage to undead)(Darkfish)

Light (Everything in this element has glow texture)

Ice (heals in powder snow)(Salamander)

Terror(can manipulate magical essences)(Soul Swimmer)

Courage

Blood(heals when it attacks)(Bloodclaw)

Toxic(immune to poison and sometimes venomous)

Underworld(piglins will not attack anything in this element)(Crimson Snapper)