Master Runicier?
Just like announced earlier, Nial completed the ten F-rank missions within a few hours. He completed them quickly enough for the receptionist in the Guild hall to upgrade him to an E-rank Adventurer without hesitation.
Afterward, Nial required a day to finish 25 E-rank missions that were interlinked to one another. In addition to that, he took four days to complete 25 D-rank missions.
Once he completed the D-rank missions, he ought to get ranked up to a C-rank Adventurer. However, most C-rank adventurers were already at the Deux-rank, meaning that Nial had to pass the assessment exam to be eligible to advance to Rank C!
"When you're ready, please inform me or my colleagues. We will let you challenge another C-rank Adventurer and if you can defeat him or her you will advance!" The receptionist told him, which caused Nial to question something.