When making a chart of the book of Revelation I was surprised to see how many different animals are described throughout the book. At times John seems to see a literal animal and describes it in the book, while at other times John uses an animal as a way to described what he sees (an example is when John says he sees a “lamb” when he sees Jesus).
Here’s a brief outline of some of the animals described in the book of Revelation.
I. BEAST
Two beasts are discussed in Revelation. The first is mentioned in Rev 11. When the two witnesses complete their testimony, the beast that comes up out of the bottomless pit declares war against them, conquers them, and kills them (11:7).

A. Beast of the Sea
Revelation 13 reveals the most material about the two beasts of Revelation. The first beast rises up out of the sea with seven heads, ten horns, and ten crowns on its horns.
Written on each head are the names of those that blasphemed God (13:1). This beast looks like a leopard but has the feet of a bear and the mouth of a lion. The dragon gives the beast his power, throne, and great authority (13:2). One head on the beast of the sea is wounded but it is healed. The whole world marvels at this beast, gives allegiance to him, and worships him (13:3-4). This beast is allowed to speak blasphemes against God and is given authority to do whatever he wants for forty-two months (13:5-6).