Joey
From Flexible Survival
Unavailable by normal means, the Joey form is granted to party members of a Kangaroo, who only wants you to be happy and safe.
NOTE: All Joey mutations on a child will instead be turned into normal Kangaroo parts. This form cannot be nativized, and its unique powers cannot be mastered. Nor can one shift into this form, even if the "Total Joey" badge is ever acquired. Party with a kangaroo, and enjoy the moment. Don't get all clingy about it.