Or do I have to subscribe or buy Premier Pro CS6, even thuogh all I'm gonna use is Encore?
Subscriptions are strictly on a "you get what you pay" basis. If you only subscribed to AE, then all you get is AE and AME.
Is Encore only bundled with Premier Pro?
Yes, Encore is available with Premiere Pro, Master Collection or Production Premium.
Europe, Middle East and Africa