HLNA Tokyo is amazing.
First things first, they have a Wahoo Taco, if you are from California that is nice but I did not bother eating at this one.
This park is amazing. It's on Odaiba Island in Tokyo, on the roof of a shopping mall. In the evening, it's nice to just chill on the roof and board. If it's any rain, this place will close.
Lesson is, if you are going to visit Tokyo and you skateboard... bring your board.