Familiar?

[View Animated Familiar Gif Here] 

First thoughts on a magical Familiar companion 

My familiar would probably be something small, quick, and easy to get away with, but with some kind of defense mechanism. I chose a common tropical lizard, but with resizable wings, and a tail that can become an unbreakable rope. There is a catch, the tail can be permanently cut off only with cursed fire, or an equally destructive element. As for the wing, it can only grow larger or smaller in certain climates. 
[These are just inspo pics, not my images]

Wing Details: should be iridescent under moonlight.




Tail details: the base of the tail should have metallic scales, since the rope that emerges from it is also solid metal, gold in color.



Chain patterns: to grab things, swing from places, maybe choke someone idk.



Concept Sketch