What the Chinese equivalent of "sucked in"?
In the sense of being satisfied/happy/delighted at someone's misfortune. Informal.

Example:
A: Did you know that John was caught cheating on the test?!

B: Really!? Haha sucked-in!

The closest in Chinese I've heard of is
幸災樂禍 but it seems a bit formal. Any thoughts?

Question

What the Chinese equivalent of "sucked in"?
In the sense of being satisfied/happy/delighted at someone's misfortune. Informal.

Example:
A:  Did you know that John was caught cheating on the test?!

B: Really!? Haha sucked-in!

The closest in Chinese I've heard of is 
幸災樂禍 but it seems a bit formal. Any thoughts?

Answer

You can use the word “活該”。

Answer

Mr. Hong's answer is perfect. I would say that too.

Answer

After asking an Australian friend, I clarified 'sucked in', which still means 'cheated, you believed me', like:

A: Santa Claus is outside on the lawn!
B: (Looks outside, but there is no Santa Claus out there) Where?
A: Haha, (you were) sucked in (by me)

There is no sense of gloating， just a dumb joke

sucked in: 骗： A：哈哈， 笑话，我骗你哦！

Answer

Is 'sucked in' Oz speak? I am not familiar with this use of sucked in. ‘sucked in' as cheated, 骗 I know and everyone knows the American 'that sucks'. How does 'sucked in' come to have the meaning you attribute to it?

لا تفوّت فرصة تعلّم لغة جديدة وأنت مرتاح في منزلك. تصفّح مجموعتنا المختارة من مدرّسي اللغات ذوي الخبرة وسجّل في درسك الأول الآن!