I think since they sold to Great Wolf Lodge you have to book a room in order to use the waterpark now.
We did a birthday package. It depends on what you want. We didnt have a big party, just family, so we got a poster on the door and a cake and $40 on an arcade card for about $80. You can go a bit more basic for less - $30 for a limited time, or you can also add on a dining credit for a total cost of $100. If you want to have a party with guests you'll need to roll your own.
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