The term "speedrun" was a very common term among gamers.
Clearing the game at the fastest time possible was considered a sport, and many Professionals liked to beat each other's records in order to show the world that they were faster than their peers.
What Thirteen was doing was similar to speedrunning.
However, his goal wasn't to beat anyone's records.
His goal was to simply reach his goal as fast as possible.
While his minions did kill the Boss Monster on the First Floor, they ignored the Boss Monsters on the Second Floor because they found the portal first.
The lower floors wouldn't pose as much threat to the Wanderers, so Thirteen was more than happy to leave the weaker Bosses for them to handle.
Aries had said that the Absolutes had managed to step into the 12th Floor.
However, none of them was able to beat its Guardian or find the portal that led to the thirteenth floor.