You can buy discounted ticket on Groupon or at a customer service desk in H-Mart next door (if you spend $50+ on groceries there). Cafeteria inside closes early, plan accordingly. Citron honey hot tea is highly recommended at the juice bar. Have fun.
Among the things that would have been useful to know: It's a very big place. The front desk and some other locations have maps. But, not only is it big, but the signage is incomplete and misleading. (Not intentionally. But if you're looking for, say, the massage area, it can be difficult to find.) So take a look at the map and figure out, generally, where things are. Other reviews have warned about this, but although you're told to make reservations for a massage, those reservations often are "lost." Mine was, though I still was able to get a massage when I'd scheduled it. I've heard of people who haven't been able to. Check your charges when leaving. I had a Groupon that included both admission and a massage. But since (see above) they had no record of my massage request and the person who took my Groupon coupon didn't return it, when I was checking out, they tried to charge me $55 for a massage. So: Make several copies of your Groupon, and watch your charges carefully.
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