The successor was planned as a Mini-Series that should have ended after 12 episode and the ending deserves to be called "The End". Nothing, really nothing is left unsolved or hidden for the next season. It has a happier ending than the "Dark Knight Rises", which was too nice in my opinion.
It looks like no one believed at Nickelodeon that it would be such a success, that it will get more seasons. To archive such a happy honey coated ending withing just 2 episodes the authors picked the oldest and worst trick in their sleeves, the Deus Ex Machina plot device. But what exactly is that plot device?
Deus Ex Machina:
A deus ex machina (/ / or / / DAY-əs eks MAH-kee-nə; Latin: "god from the machine"; plural: dei ex machina) is a plot device whereby a seemingly unsolvable problem is suddenly and abruptly solved with the contrived and unexpected intervention of some new event, character, ability, or object. It can be roughly translated as "God made it happen," with no further explanation, and, depending on usage, is primarily used to move the story forward when the writer has "painted himself into a corner" and sees no other way out. However, in other cases, it is used to surprise the audience, or, commonly influenced by editors and/or publishers, bring a happy ending into the tale.
Source - Wikipedia
Using a Deus Ex Machina is the worst you could do in your story to solve a conflict. It isn't foreshadowed, not clearly planned before and makes it too easy for the character to gain what he desires. It nullifies all the previous attempts and conflicts and let them seem valueless. Look out in your own stories if you have such a moment, because the only reason for creating them is a lack in ideas in how to resolve it in a explainable way, that the character could actually archive in his current situation. Its a cheap way and could left a bitter taste in the readers mind as it did to my in this case.
And at the end I have another question prepared to you regarding the main topic of this post.
Did you find the happy ending satisfying?