By imbuing this glowing green liquid, you have been infused with the radioactive power of mutation!
*You can feed on radiation and are immune to any negative effects of radiation.
*You can infuse at anytime different animals into your form, allowing you to manifest traits and powers of those animals as you wish. You can control your appearance as to make yourself as monstrous as possible, make yourself look attractive, or even hide the mutations completely. There is no limit to the amount of traits you can manifest, although it does become harder to control how you look the more mutated you become.
*You can also grow typical fictional mutations and powers. Anything from arms covered in fire that throw fireballs, to a sludge body, to explosive crystal protrusions,. In general however the more versatile the power the weaker it becomes. But this can be mitigated with obvious physical changes to boost its power. For example just given yourself psychic abilities with no physical changes means you might have double your physical strength in telekinesis, given yourself a frail body with an oversized head would amp your psychic powers to the point you were a telekinetic juggernaut that could throw tanks and that could mind control hundreds at the same time.
*By focusing on one animal you can assume a mutated giant form of that animal, from anywhere from 3x to 6x the size of the original creature. In this form you can only use other animal forms to give yourself extra abilities, but the abilities of the first form are greatly enhanced. You can fuel this gigantification with your radiation powers, become truly kaiju size if you want to use the energy to become so.
*Animal abilities are based more on comic book physics than real physics. A pair of wings will allow you to fly and at great speeds, even though realistically you should still not be able to fly all that great. Abilities are enhanced at a moderate comic book level; the acid of an insect might be strong enough to melt though bank vaults when you use it. The more you change your physical body the stronger these abilities become.
*You start out with a genetic database of every animal you've ever touched or eaten. You can gain more though touching or eating animals.
*You can admit a glowing green radiation that can be used to mutate animals or people in similar ways to yourself. Just about any change you can do to yourself you can do to another being, although with much the same rules. These creatures are normally under your control, although human and other sapients can resist if their wills are strong.
*You also can also use this radiation in many other ways, such as blasts, force fields, an aura that allows you to fly, ect. With time and training just about any weird radiation trick from fiction can be mimicked. But the more powerful and esoteric, the more energy and hard work it will acquire.
*By taking in the energy of a nuclear plant or explosion all at once, you can use that power to make a glowing green portal and travel to different places or even different universes. Your target universe can be anything within fiction, or even just worlds that are the "closest" to you that fit your wishes. Without some strong source like the two above it would take at least a year to store this type of energy for use, however.
*You can also cure and render people immune to radiation poisoning.