Ratatosk

Ratatosk is the Lord of Monsters, as stated in Tales of Symphonia: Dawn of the New World. He is also the Summon Spirit of the Great Kharlan Tree, which was destroyed in the previous events of Tales of Symphonia.

The Distribution of Mana
Some ten thousand years ago prior to Tales of Symphonia: Dawn of the New World, both the present worlds of Sylvarant and Tethe'alla were still one. However, even this far back in time, mana hadn't existed--it was only after the arrival of giant meteor, Derris Kharlan, that mana had actually been born into the world.

Observing that the overwhelming energy from the ethereal comet would no doubt negatively affect the world, Ratatosk called upon the eight Centurions: Lumen, Aqua, Solum, Tonitrus, Glacies, Ignis, Ventus and Tenebrae. Along with his own power, the nine were able to evenly distribute and balance the flow of mana throughout the world. Ratatosk subsequently created monsters in order to sustain that balance, which lasted several thousand years after that.

Trivia

 * Ratatosk's name comes from Norse mythology. Ratatosk is a mythological squirrel that is residing in Yggdrasil, the tree of Midgard. His duty is to carry insulting messages between Nidhogg the dragon that lives under the tree and Veldronir the eagle who lives on top of Yggdrasil.