Did a quick search and found the same question asked on Reddit. I think the power has been printed in at least one other source as well, but here's at least one of them:
SHIFT
Type: M Action: Complex
Range: Self Duration: Special
This power allows the critter to take on the shape of a specific animal or metahuman, and back to its original form. The critter’s attribute ratings carry over to the new form, as do any purely internal deltaware implants; non-deltaware implants are automatically rejected during the change, causing (total Essence cost of implants x 10, round down)P damage—the character does not recover the Essence from implants lost in this fashion. Purely cosmetic alterations such as piercings and tattoos are lost as well, though this does not injure the critter. When in their new shape, the creature gains access to all non-paranormal abilities innate to that race, including Armor, Natural Weapons, and Enhanced Senses, if any. The creature retains all of its paranormal powers in its new form. Once the critter uses the shift power, it remains in its current form until it decides to shift back. The critter does not suffer a –2 penalty for sustaining this power. This power only affects the creature’s physical form, not its clothing or equipment; the process of the change destroys most fabrics.
Aetherology page 38
