After temporarily bidding farewell to the mysterious dark elf knight Kizmel, Kirito and Asuna set out and arrived at the fourth floor of Aincrad. The world on the fourth level is filled with countless "waterways". The two finally reached the urban area by "swimming". What they saw were streets floating on the lake and countless gondolas of different sizes. After the mission prompts, they learned that if they wanted to move freely on the fourth floor, they must first obtain a gondola boat dedicated to them. In order to obtain shipbuilding materials, Kirito and Asuna challenge the giant fire beast "Giant Sloth"! At this time, a person they did not expect was waiting to meet them again on the fourth floor...
