The place is huge. Buy ahead if you can, but I imagine you'll probably be fine if it's not a holiday.
Buy tickets when you arrive is fine
They have a box office with set times for the dinner/show but like Luis said, you risk them being sold out (which is a rarity when I've been).
You can buy tickets at location but you risk location being fullm best to purchase prior
Pre book will help on busy days
You dont need to pre book but it may help on busy days
You can buy at box office, but it may be sold out when you arrive and you can get online discounts.
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