When I tried to strengthen [Rusted Sword], it turned into a ridiculous magic sword. nu none raws https://ncode.syosetu.com/n1199gc/ description n this world, when you are 12 years old, you will be given a special weapon called a "sacred weapon" by God. Last, a boy living in a remote village, dreamed of becoming an adventurer with his childhood friend Ruby. Then, in response to the "Blessing Ceremony" that was given the "Sacred Treasure", Ruby received the highest A-ranked sacred treasure, but the last received the F-ranked tattered [rusty sword]. Unlike his childhood friend who was invited to a leading party, he was told that his dream of becoming an adventurer would not come true, but he decided not to give up and fight with a [rusty sword]. Defeat weak monsters little by little and steadily strengthen the [rusty sword]. After three years, the Rusted Sword finally reached weapon level 10. At that time, one skill awakens to the [rusty sword] and "evolves" into a ridiculous magic sword. This is a boy's upstart adventure that has been said to be the weakest