Fire Wand Achievement in Vampire Survivors

This must be done in one run. Light sources are, for example, torches in the first stage, and you'll find them dotted around the map. You'll need to line up whatever weapon(s) you currently have to destroy them. They only take a hit or two, and they always drop some sort of resource, so it's in your best interest to destroy them anyway. After destroying 20 in a run (which will likely happen without you even trying to do so), you'll unlock this achievement.