- "The one who guards the Deep Sea Opal is known as the Rainbow Serpent."
- ―Sao Feng
The Rainbow Serpent was a large serpent that lived under the sea. The serpent was stuck in an undersea cave guarding the mystical Deep Sea Opal. The giant snake's scales were of bright colors, which earned it the name the Rainbow Serpent. Jack Sparrow encountered this beast while searching for the Deep Sea Opal for Sao Feng.