Protactinium is a highly toxic relatively stable radioactive element. It only used for scientific research and is usually a by-product of nuclear energy and research. It’s bioactive and reacts readily with organic compounds and oxygen.
Servals are medium-sized carnivorous cats. They will hang using their hearing and can bring down larger prey. They generally avoid other large cats. They are paired with protactinium as servals have been known to be very vicious.
Uranium needs almost no introduction. It’s a mildly to very radioactive element, but very useful element, mostly used in nuclear reactors, scientific research and medical machinery. It can also be used for hardening, plating and in alloys.
Black Panthers (or leopards but not Jaguars) are large cats live in Africa and Asia. They are stealthy jungle hunters, and capable of hunting large prey as a apex predator. They are tied with Uranium as Africa is a major exporter of Uranium and I felt the pather reflected the raw power of Uranium.