We did decide upon +2. I'll
update it.
I found the following
here:
An adult opossum is 2 to 3 feet long and weighs between 4 and 12 pounds.
That's the size of a Virginia Opossum (
Didelphis virginiana), the largest species of Opossum. I would like to lower the minimum weight a bit or point out these are big examples. Oh, and we should mention the length includes the tail...
This entry represents the larger species of opossum, about the size of a cat. Such opossums are typically 2 to 3 feet long (up to half of which is tail) and weigh between 2 and 12 pounds.
I'd also suggest modifying the description and tactics a bit:
Opossums are omnivorous marsupials that can live nearly anywhere they can find food and dry, secure places to den in. An opossum will use a number of dens within its home range, they usually lair in hollow trees and logs, brushpiles or the abandoned lairs of other animals. A nest of leaves and grass is usually made at the den site.
Opossums feed on insects, earthworms, small mammals, fruits, grains, plants, and carrion.
This entry represents the larger species of opossum, about the size of a cat. Such opossums are typically 2 to 3 feet long (up to half of which is tail) and weigh between 2 and 12 pounds.
An opossum familiar grants its master a +2 bonus on saving throws against poison.
COMBAT
If threatened, an opossum will try to escape up a nearby tree or feign death. If cornered, it exhibits a threatening posture, hissing and making low growls. A desperate opossum may bite.