Tunneler toad

The magical creature called a tunneler toad, lives deep within the Xlotic desert. They live in a series of hidden worlds left by some forgotten ancient civilization, called Ishmali Reservoirs by the ancient Ikosians, because they seem designed primarily as water reservoirs. They're basically large caverns full of water, enclosed in their own pocket dimensions. The reservoirs are largely uninteresting, but the tunneler toads themselves have a curious ability to detect pocket dimensions and enter them with ease. In their natural habitat they use this to pass in and out of the Ishmali Reservoirs as they please, using them as a hidden nesting ground, but the ability is said to be usable on any pocket dimension they come across.(ch.87)