Geometric Mage: First Spell, Circle

"Hey monster, you're not ready for this blow, but I don't give a shit!!" said Lian as he drew a circle inside another circle in his mind.Then, a few seconds later, a fireball as big as a house hit a monster just over 4 meters tall...It was a waste of resources, but it was damn fun!"BOOM!!!" he said as the fireball reached the monster, covering it entirely.The excitement on his face was palpable as his clothes and hair fluttered from the power generated by the impact.[Accuracy: 97%]"Tsk, it's really hard to achieve 100% accuracy when casting spells... that just means I have to do better!"Meanwhile, the monster and the entire area around him was destroyed. The crater was huge, flames burned the ground, and ash mixed with dust covered the air.---In a world full of Gates, Mages and Knights work together to defend humanity from extinctionLian, a boy from a small town, awakens a very... unique system.Casting spells by drawing strange shapes in his mind had become normal for him by now.Thanks to the system, he had become a Mage, a human capable of using mana to cast spells.Facing monsters from the Gates had become routine. Studying magic was a pastime. After all, he had the System, he didn't need to study classical magic. Or maybe not...