MTL - The Roots of Manga - Chapter 211 clue

Once upon a time, the Land of Promise thrived under the cycle of the four seasons change. Until a vengeful enchantress cursed the land, and divided it into four realms each with a ruler to bear its burden.The people suffered for years under the endless heat in the Summerlands, the bitter cold in the Winterlands, the never changing bloom in the Springlands and the constant fall in the Autumlands.A prophecy whispers of a marriage between a king and queen that will release the land from its curse and unite it under a single kingdom.Princess Caroline is forced to marry the Summer King, will she be able to fight for a peace amidst a court full of power hungry nobles and will she succumb to a burning love in the arms of a fiery warlord?

A world with magic, mythical creatures, mystical herbs, labyrinths, and treasures.A world where the strongest adventurers get to be the ones to enjoy fame and riches.A world where various rankings decide your worth.This is the world where Shye Crowley and his sister were born.As the children of two fairly known diamond-ranked adventurers, Shye and his sister, Maia, enjoyed a prosperous lifestyle.Unfortunately, after departing for a mithril-ranked quest in hopes of ranking up, their parents couldn’t return.Years passed and life went downhill fast for the siblings.Fortunately, a fateful encounter bestows him a system that could change their fate.

In this period where countless supporting lead actors always attempt to counterattack, turn over a new leaf or simply refuse to take up the role, his purpose of existing is to fill the role of a good supporting male lead and uphold his duty to the best of his ability. To add the needed lustre to storylines and this world. Only, it’s a pity that someone who is not afraid of god-like enemies will be afraid of pig-like teammates.

Bitterly, he realises that for some unfathomable reason, he is being bothered time and again by a bastard who refuses to follow the script… In order to walk the path of a good supporting male lead, he engages in a battle of wits and courage with that person. Loving each other and killing each other, one ultimately cannot escape fate’s teasing– why is it so difficult wanting to be a responsible and diligent supporting male lead?! QAQ

- Description from novelupdates

Waking up in the body of a 6-year-old boy a few years before Cintra is destroyed, Madara receives a system that gives him the ability to gain the powers of Uchiha Madara.[The peak of Uchiha Madara's system is before he becomes the ten-tails jinchuuriki.]The system's percentage does not stop Madara's power, but rather the system's release. After all, I don't want to see a character who goes around killing everyone from the beginning of the story.