Lin Fan summoned out Igneel to bring Yun Lan and the kids back to Dungeon City.
If he were to bring them back in the carriage, it would take more than two months since he would have to travel slowly for the kids.
With Igneel, he would be able to fly past most of the problems that he would have encountered otherwise. At the same time, he would be able to entertain the kids so that they wouldn't cause any problems.
The moment that the kids saw Igneel, they were completely taken by it.
They rushed onto its back and then started moving in different directions to stare out at the scenery around them.
Of course, Lin Fan couldn't let them fall, so he created a spiritual energy barrier around them that prevented the wind from blowing them off.
This might have been draining for someone in the Qi Gathering Realm, but it was nothing for a Foundation Realm Cultivator like him.