What is the rarest animal in universe?

The rarest animal in the universe is one that has never been seen before, and may not even exist. However, there are some animals that are considered to be extremely rare, such as the giant squid, which can grow to be over 40 feet long and weigh over 2,200 pounds. Other rare animals include the snow leopard, of which there are only around 4,000 left in the world, and the Sumatran tiger, of which there are only around 400 left in the world.