It took close to six hours before they reached the first oasis. It wasn't because of the distance, of course - if they were to walk casually from the Gate, even with the heat and the sand hindering the trek, they should be able to reach it in less than half an hour… But it was impossible to travel fast under the current circumstances.
The monsters were the problem. As the dungeon was overpopulated to the point it could lead to a dungeon break soon, the place was naturally filled with monsters. And not just any monsters - one of the two apex predators of the C-rank dungeon, the scorpion mantis, as it was generally described in the reports. For Damien's team, which mostly consisted of B and C-rankers, facing so many relatively strong foes was not an easy task. Perhaps it would have been easier if Damien chose to use his ability more instead of relying on the sword, but…
Regardless, Lane didn't complain. Thanks to Damien holding back, he could have more fun himself.