Unusually, these animals seem to have been affected but little by the Prometheus Virus. They still hurt, though.
The Jellyfish's body is covered in completely transparent flesh. Their head is large and dome-like, much like a mushroom. One has no mouth nor any nose. Their body is long and wide, but somehow still sturdy enough to traverse land for brief periods of time. You can see all of their internal organs through the transparent skin and muscle. Their arms are a collection of tentacles tipped with stingers. Their legs are even more tentacles with just as many stingers. These tentacles are much stronger, capable of twisting together to form crude legs for brief excursions on land. One has a jiggly, jelly-like ass.