You can find all of them in or around the mansion area after your fight with Wagbert. You might want to be careful when getting there, since you need a low corruption level to get the correct ending.
Is there endings to this? I got to wagbert, got new ability, but haven't been able to get anything else to happen outside of the slime dragon randomly appearing in that one room, but now collars are all there with a slime dog there. Can't find any other changes anywhere else, or keys, or anythin
