Just thinking about it, if Wei Xiao Bei could give his bred creatures [Flame Immunity], then any creature that he bred might not be able to bathe in lava, but they could stay there for a period of time. Although they would receive some damage from it, the damage would not be too great.
After all, the temperature of lava was not that high. Lava that had just been erupted was around 900 to 1200 degrees Celcius.
Moreover, the further the lava flowed down the volcano, the lower its temperature would be.
Normally, the temperature of white lava was 1150 degrees, golden was 1090 degrees, orange was 900 degrees, cherry pink was 700 degrees, and dark red was 550 degrees.
On the other hand, [Flame Immunity (Low)] could allow the host to resist damage from temperatures below 600 degrees. Damage between 1500 degrees and 600 degrees was decreased by 90%. For any higher temperatures, there would be a 50% decrease in damage.