Winner: -ThatOneWarriorFan-
Correct Answer: Longtail

~~~
In the beginning, I was a kittypet,
I was quick to pick up on things,
Slowly I rose to fame,
And I was known in all Clans.
Who am I?
~~~

Remember to vote! Voting, liking, whatever you call it is a way I know you liked the last riddle and you want me to continue this book!
~Night