Chapter 166: My Water Affinity Talent is back?
Aiden can see they are using the gas burner to boil the water used for the noodles they are going to eat; he didn't say anything because, with the amount of mana they have, they are capable of boiling the water. It needs a flame of a particular temperature for minutes to boil.
If they just used the intense heat of their mana in one go to try to heat the water, the only thing that would happen would be that there would be steam, not boiled water, and he doesn't think they have enough mana to maintain the spell that long.
He remembers he had awakened an FFF+ grade Fire affinity earlier, after having seen one of the ladies casting a spell during the fight; with that, he has also awakened an Earth affinity of the same grade, but he didn't think that would be useful for now.