Any ideas on how they could be added? Behaviour? Drops? Achievements related to them? Are they aligned with anyone? Do they have an ability is some sort? Tameable? Are they based off the Hobbit movie versions, or do they take on a new design?
Questions like this are important to a suggestion, and help to further instigate discussion, which makes the suggestion better still. Short suggestions like this, for things as large as Wereworms, are not advised.
Apologies if this seems in any way rude, for I am not trying to be.