Radioactive spiders are everywhere these days, good business for the exterminators. You’re possessed of the physiology of an Inheritor, including flight, super strength, speed, reflexes and durability enough to hunt the Totems that are a staple of your diet.
The main feature of your new physiology however, is the ability to absorb life energy. This absorption further enhances your other abilities in line with the general quality of the energy absorbed. Animals provide barely enough energy to survive, regular humans can barely sustain you and your abilities, but powered humans can enhance your abilities after absorption. The very peak of this being Totems (the most common being Spider-totems), which contain a vast amount of energy capable of enhancing your powers for great lengths of time. The Inheritor Morlun, for instance, was able to move faster than the preternatural ‘Spider-sense’ of many Spider-Totems after having gorged himself on them.
This sensitivity to life energy also allows you to track the life energy of those you’ve felt before, ensuring your quarry will never escape. The pinnacle of this sense is the ability to traverse the Web of Life and Destiny as a means to track your prey. While this was originally intended to allow you to traverse the multiverse in pursuit of a totem to feed on, It also acts as a form of generalized multiversal travel through the web, as almost every universe has at least one Totem within it.
Finally, as long as you have a steady amount of life energy, you cannot die, and will heal from wounds (though you will require more energy than usual).
Unfortunately, these powers come at the cost of necessitating the absorption of life energy to survive. While surviving off of animals is possible, as is not killing hosts while feeding, both will severely weaken your new physiology. Similarly, unless you possess a strong will the feeling of feeding will become highly addictive.