I agree with the fast pass, we did that, also we got there right after they opened, not much of a line and we got right in, didn't have to wait much for the group ahead of us because it wasn't super busy yet.
There is a group discount of $3 off each ticket if you have a group of 15 people or more.
The entry fee is $25 each $31 for the fast pass. You don't have to make a reservation. Everyone has to wait in the first line to get in, even if you get a fast pass. I don't know if there is a group discount. But I suggest on getting the fast pass though. We waited only 5 minutes in line with the fast pass as opposing to 1 hour. Hope this helps!:)
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