23. Giant Manta Ray
Giant manta rays are the giant versions of stingrays and they can reach up to 7 meters or 23 feet in length. Their appearance is in fact what makes them terrifying because they are surprisingly docile, although there have been cases of ray attacks. Most famously, Steve Irwin was attacked and stabbed in the heart with the sharp barb they have underneath their tails. Although attacks are rare, they are extremely dangerous because most of the time the sharp teeth-like edges can get caught in the wound.