If i build something in the wild, will lightning catch it on fire? Does it lightning in snow and desert bioms?
It could get caught on fire by lightning but, it won't if you make it in a ice or dessert biome since it doesn't rain there.
Will wood stairs catch on fire? Will lightning strike and catch the building sides on fire? Or does lightning strike straight down? I don't want to build something in the wild and have to worry about it being burned down.
The greatest chance for having lightning burn down your wooden/woolen home is if you are in a desert/arctic biome right next to a biome that has lighting. The lighting will strike your home, but because there is no rain, it will not be put out automatically. My wool roof in the LLO Jungle has stood for over 10 months now, and I think it is because the rain puts it out when it gets struck by lighting.
Lightning can definitely burn down houses, though it normally only happens in Deserts. Wilderness Spawn can attest to that.