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Definitely Niffly as well, I love how mischievous they are, but they also seem to be understanding. They are basically a good mix between a cat and a dog with a lust for gold. As an added bonus they also look very cute.
Its really hard to say what is my favourite beast i love, all of them are so beutifull (ok ... yes Bundimum is also from a certain perspective). Lot of them are forgotten and lot of them on the verge of extinction. For me is all beast my favourite, although some of them may seem aggressive or insidious, It is important understand them