All the monsters that Jason had killed so far were all Pawns, and Jason knew that even though they were stronger, they wouldn't even hold a candle to the other classes!
Just to upgrade from Pawn Rank III to Rook Rank I, Jason needed to get two thousand kill points! It was four times higher than what it took to upgrade from Pawn Rank II to Pawn Rank III, and that number told Jason that the upgrade was going to change everything about the monster!
Right now, Jason's strongest monster was on the same level as a Country-level Eldritch Rank, the same as the Red Gate Boss. But it was still far weaker than what Jason knew he needed. A Red Gate boss wouldn't even put up a good fight against an A Rank, and Jason knew that if he fought against a guild with high-ranking members and they had a supporter who could boost their strength, then they would be able to beat his Legion.