This is based on a discussion that was had amongst a few players in Discord and some subsequent testing IG. Similar to the way that the bird forms have access to the climb tool, some of the forms would benefit from having access to the dig tool. For example, the Badger form would make sense, potentially some others.
Not to Hijack it, but in a similar vein, could we consider maybe a Boulder Throwing tool? - That seems like a perfectly reasonable thing to be able to do in (certain) polymorphed forms but since Boulders currently operate on a unique power, no dice unfortunately.
This has been brought up many times and, for what it's worth, has my endorsement every one of those times.