Arcane beasts
Lore:
In this arcane universe the gift of magic was provided solely to humans, even now the only creatures that can use magic are humans
After Durzas attack polluted the entire world, the magic energy started to inhibit non magic creatures in subtle ways, diversity dropping and mostly smaller animals surviving in the wild,the maximum size on land was just under a ton and was achieved by a large bull
It was different in the sea as many sea creatures managed to suppress the magic and grow to normal sizes, with descendants of a certain shark managing to utilise limited forms of magic
But every once in a while certain animals will be born that have the power to utilise said magical energy, and absorb it to a great extent
Such creatures after reaching maturity search for beings with magic and hunt them down and by doing so absorb their magic energy
They are extremely dangerous and will appear once in a century or so but are even rarer due to dying to the wild before reaching maturity
They possess great control over magic and will only grow more powerful and experienced if let be and continue to hunt magic beings(humans mainly)
The only known instance of this is a reptilian creature simply known as the Tarasque
It took an entire fleet consisting of combined military from various kingdoms and the military might of a church along with several curse users a week to be finally put down after being cornered, it destroyed two entire island populations along with a militia led by a curse user in the process