Many on the list of crazy animal adaptations have outrageous tools to hide from predators. Cuttlefish and leaf bugs, for instance, are absolutely unparalleled when it comes to camouflage and mimicry, while many young white-tailed deer essentially pretend to die in order to dissuade hungry killers. Others go a bit more extreme to piss off their enemies, such as Northern Fulmars, who vomit a disgusting liquid, and Pistol Shrimp, whose claw snaps and ignites a collapsing bubble of epic proportions. Other wacky adaptations found in animals range from the mere existence of an electric eel, as well as hooded seals who inflate a pink balloon from their noses to attract a mate.
When you're starting to attack one of these Texan lone stars, don't be surprised if it shoots out a stream of blood from its eyes. Even if its in the mouth of a fox, the autohaemorrhage adaptation is so disgusting, the fox will drop the lizard because of the bad taste and trauma.
If you go to the Mediterranean, check out the rare "immortal jellyfish," which has evolved in ways that make us question reality. These little jellyfish start as sexually immature animals, reach sexual maturity, and then have the distinct capability to indefinitely revert itself back into that sexually immature stage all over again.
Wombats leave a crapton of crap around its environment, often up to 100 a night. Those droppings come in the shape of cubes in order to mark their territory that distinguishes their turds from those of any other animal in the world.
This adaptation is perhaps the most intense defense mechanism: suicide. When the Malaysian Exploding Ant decides that its life is at risk, it will often click its own self-destruct button and say, "If I'm gonna get murdered, it better be by me."