Horse back riding during a volcano raining keeps my horse safe from being burned

This is about how I'm going horsebackriding but suddenly it starts erupting of a volcano unfortunately luckily it rains and cools it off but their ears are very good at hearing so he gets scared of the noise of lightning. There aren't any seatbelts so i hang on tightly when he freaks out. His ears are sensitive because they are standing up. Trying not to get hit by the fire of lava I keep jumping hurdles over the fallen tree logs and puddles of mud to not get dirty.