Spiders
There is such thing as a spider called a benutriabodiencis, (BEN-OO-TREE-U-BO-DEE-EN-SIS). Its body contains poison that changes your personality when it bites you. It also included side effects that happen when you don't notice. You might not notice that you have changed, but other people might notice once you do act different for a long time. To avoid the spider, put on bug spray before going out to forests or the woods.
Some spiders possess toxins to protect themsevles from dangerous animals and predators. Some spiders have designs on them that helps blend into other colours to trick other animals that want to use spiders as their prey. Some spiders could grow another leg if one of their legs snap off. Spiders inject their venom into other prey to kill it so than they could eat the prey. They sometimes might use the same venom to injure or kill their predators.