Unity 5 - new Animator State machine behaviour: ca we use UnityScript?

Questions & Answers
1

Is that possible? Are you forced to only use C#?

Even if I end up learning C#, the whole project is written in Javascript and I have the Script Execution order set to compile C# first so I wouldn’t be able to access any of my scripts, right?

UPDATE:
I just realized how unclear I was, I’m referring to Unity 5 new Animator feature:

2

95% sure you can’t use .js for this. You may still be able to achieve what you want without converting your whole project to C#, (refer to the document I linked in my comment if you’re having trouble) but these StateMachineBehaviour things need to be written in C#.

Not as intimidating as it sounds. There’s a lot of overlap between the two languages, many differences are minor, and you won’t need to learn all the major differences immediately.