How could the campfire
warm things by conduction and radiation?

The heat can tranfer both directly and through electromagnetic waves.

Explanation:

Explanation:

Radiation is what occurs when energy is transmitted or emission of energy through the space or in the form of waves. This includes: electromagnetic radiation, such as radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and gamma radiation

Conduction is a a more so physical contact situation but if connection to the ground is made then the heat can transfer into the ground and proceed to spread into a wider vicinity  warming the general area around it in a more physical manner.

i guess the game developers wanted to give off a more gamey/cartoony feeling without trying to copy fortnite exactly