Rivet uses each of his different tails for certain reasons.
Aquatic: rivet uses this tail for swimming and underwater missions
Lizard like: Rivet uses this tail for gripping things
Fluffy ringed: this tail helps rivet to be able to use gadgets and charge them as they have a magnetic pulse in them
Long fluffy: Just a floofy tail because who doesn’t love floof
Short nub: this is rivets regular tail it’s just a cute nub ❤️