In this castle, Rex learned many things. The castle itself stood five times taller than the world he once knew, and it was home to beings who were not human. Everyone here sought power — everyone trained to become the strongest within the castle.
Rex had decided one thing:
He would no longer be the weak, pitiful person he used to be.
He would become strong.
For two months, Rex underwent harsh training. He even fought against a five-meter-tall beast with razor-sharp white fangs. Through endless effort, his strength rose from E-Rank to D-Rank.
There were power levels in this world:
E, D, C, B, A, and finally… S-Rank.
E was the weakest — S was the strongest.
And now, Rex had finally reached D-Rank.
One day, while Rex was training, the knight — whom he hadn't seen in two months — approached him.
"You've grown stronger, Rex," the knight said.
Rex nodded.
"I'm not the same person I used to be."
The knight smiled.
"You will now enter your first dungeon. Inside, you can obtain magical jewels. With them, you can gain new powers — and strengthen your armor and sword."
Without hesitation, Rex set off toward the dungeon..