Jujutsu Kaisen: The Flame Mage Who Starts with Gacha Pulls

Traveling back to the world of sorcery and war, I awaken the Flame Mage System.
Defeat powerful enemies to earn points and extract various fire abilities.
King's Flame, Great Fireball Technique, Flame Breathing, Crimson Magician...
But why is the timeframe when Itadori entered school?!
Six months later, I'll be performing Su Nuo? Really?!
In order to save his own life, Tokiwa Ryuichi decides to use his talent, which is comparable to Gojo Satoru's, to change the world line.
Gojo Satoru: Ryuichi's talent is no less than mine, and it's only a matter of time before he surpasses me.
Atsuya Kusakabe: Is he the strongest after Satoru Gojo...? He certainly has that strength.
Yuta Otsu: Although he is a junior, Ryuichi does have a convincing power.
Ryomen Sukuna: Tokiwa Ryuichi... maybe he'll be a bit tricky, but I'll win. I'm the strongest, after all.
Absolute power, and the loneliness that comes with it, will teach you how to love...
Wait, what does "epic enhancement of the brain" mean? What does "five calamities" and "four knights" mean? What does "twenty fingers + incarnate Buddha + ten shadows + flying + divine martial arts to unleash the complete Su Nuo" mean?!
Tokiwa Ryuichi is under a lot of pressure facing this jujutsu world that is starting to go in a strange direction.
[Follows the main storyline, weak system, some original content.]