I have two made-up creature to suggest:
The first is called a Serangor, and it is I guess sort of similar to the Tienko's, but they have split tails and look like either Leopard's, Tigers, or black panthers. Here's what the General description could be:
Serangor are elusive in their home in the Etain Desert. When they do grant an egg it is because the Magi has either helped them or has done a great good. Unlike some creatures, Serangor's are peaceful all the time, until you come too near their eggs. With sharp fangs and long canines, any Magi who doesn't steal one when the parents aren't looking is a goner. Rare even in the forests they call home, these cat-like creatures keep on good terms with most Magi. Famed also for their double-tail, they are stubborn creatures and are not easy to train. They can use their split tail to pick up or move objects.
The second one is called an Articun. It is a horned cat that can tell the quality of a person. They may or not act on this judgment, but they are usually aligned towards being good creatures. Here's what their general description could be:
With pelts a deep black striped with what looks like lava, Articun are something to fear is you are a bad person at heart. Living in the deepest part of the Etain Desert, these elusive beasts are never seen. A Magi is blessed if a pair gives them an egg. These creatures are said to be able to see the heart of a person, whether it be good or bad. A spiraling horn atop their head sits on the head of a lion, and neck and body of a panther with hot lines of fiery skin. These creatures save travelers from the wild Serangor on occasion, though they are kin to the mighty felines.
. Other mystical creatures Hydra, Lightening Dragon, manticore,
Ninja'd
I love the frog 
